U.S. patent application number 12/111340 was filed with the patent office on 2008-11-13 for abrasive filament and brush.
This patent application is currently assigned to 3M Innovative Properties Company. Invention is credited to Yeun-Jong Chou, Dean S. Holmes.
Application Number | 20080280541 12/111340 |
Document ID | / |
Family ID | 39580635 |
Filed Date | 2008-11-13 |
United States Patent
Application |
20080280541 |
Kind Code |
A1 |
Chou; Yeun-Jong ; et
al. |
November 13, 2008 |
ABRASIVE FILAMENT AND BRUSH
Abstract
An abrasive filament including a matrix of thermoplastic
polymer; and a plurality of abrasive particles such as eutectic
alumina zirconia particles interspersed throughout at least a
portion of the matrix. Abrasive brushes including such abrasive
filaments are also disclosed. Methods of deburring a substrate
having at least one burr, with a brush, the brush having bristles
including eutectic alumina zirconia particles and a matrix of
thermoplastic polymer, wherein the method includes the steps of:
contacting the substrate with at least one bristle of the brush in
a contact region; and inducing relative motion between the
substrate and the at least one bristle.
Inventors: |
Chou; Yeun-Jong; (Woodbury,
MN) ; Holmes; Dean S.; (Ellsworth, WI) |
Correspondence
Address: |
3M INNOVATIVE PROPERTIES COMPANY
PO BOX 33427
ST. PAUL
MN
55133-3427
US
|
Assignee: |
3M Innovative Properties
Company
|
Family ID: |
39580635 |
Appl. No.: |
12/111340 |
Filed: |
April 29, 2008 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60917172 |
May 10, 2007 |
|
|
|
Current U.S.
Class: |
451/59 ; 451/466;
451/526 |
Current CPC
Class: |
A46B 2200/3093 20130101;
A46D 1/00 20130101; A46B 13/003 20130101; B24D 3/28 20130101; B24D
13/10 20130101 |
Class at
Publication: |
451/59 ; 451/526;
451/466 |
International
Class: |
B24D 13/02 20060101
B24D013/02; B24B 1/00 20060101 B24B001/00; B24D 13/04 20060101
B24D013/04; B24D 13/06 20060101 B24D013/06; A46B 15/00 20060101
A46B015/00 |
Claims
1. A method of deburring a substrate having at least one burr, with
a brush, the brush comprising bristles comprising eutectic alumina
zirconia particles and a matrix of thermoplastic polymer, wherein
the method comprises the steps of: contacting the substrate with at
least one bristle of the brush in a contact region; and inducing
relative motion between the substrate and the at least one
bristle.
2. The method of claim 1 further comprising applying a lubricant
adjacent the contact region.
3. The method of claim 1, wherein the substrate comprises carbon
steel.
4. The method of claim 1, wherein the brush further comprises a
securing element that functions to secure the plurality of abrasive
filaments to form a brush and the method further comprises mounting
the securing element to an apparatus capable of inducing the
relative motion between the substrate and the at least one
bristle.
5. The method of claim 1, wherein the matrix of thermoplastic
polymer comprises a polymer selected from polyamide and
thermoplastic elastomer.
6. The method of claim 1, wherein the eutectic alumina zirconia
particles comprise from about 35 to 45 percent by weight of
zirconia.
7. The method of claim 1, wherein the abrasive filament comprises
about 55 percent to about 75 percent by weight of thermoplastic
polymer; and about 25 percent to about 45 percent by weight of
eutectic alumina zirconia particles.
8. A method of refining the surface of a substrate with a brush,
the brush comprising bristles comprising eutectic alumina zirconia
particles and a matrix of thermoplastic polymer, wherein the method
comprises the steps of: contacting the substrate with at least one
bristle of the brush in a contact region; and inducing relative
motion between the substrate and the at least one bristle, wherein
the efficiency is at least 1.0.
9. The method of claim 8 further comprising applying a lubricant
adjacent the contact region.
10. The method of claim 8, wherein the substrate comprises carbon
steel.
11. The method of claim 8, wherein the brush further comprises a
securing element that functions to secure the plurality of abrasive
filaments to form a brush and the method further comprises mounting
the securing element to an apparatus capable of inducing the
relative motion between the substrate and the at least one
bristle.
12. The method of claim 8, wherein the matrix of thermoplastic
polymer comprises a polymer selected from polyamide and
thermoplastic elastomer.
13. The method of claim 8, wherein the eutectic alumina zirconia
particles comprise from about 35 to 45 percent by weight of
zirconia.
14. The method of claim 8, wherein the at least one bristle
comprises about 55 percent to about 75 percent by weight of
thermoplastic polymer; and about 25 percent to about 45 percent by
weight of eutectic alumina zirconia particles.
15. An abrasive brush comprising: a plurality of abrasive
filaments, said filaments comprising a matrix of thermoplastic
polymer and a plurality of eutectic alumina zirconia particles
interspersed throughout at least a portion of said matrix; and a
securing element that functions to secure the plurality of abrasive
filaments to form a brush, wherein the abrading efficiency on a
workpiece is at least 1.0.
16. The abrasive brush according to claim 15, wherein said matrix
of thermoplastic polymer comprises a polymer selected from
polyamide and thermoplastic elastomer.
17. The abrasive brush according to claim 15, wherein the eutectic
alumina zirconia particles comprise from about 35 to 45 percent by
weight of zirconia.
18. The abrasive brush according to claim 15, wherein said abrasive
filament comprises about 55 percent to about 75 percent by weight
of thermoplastic polymer; and about 25 percent to about 45 percent
by weight of eutectic alumina zirconia particles.
19. The abrasive brush according to claim 15, wherein said abrasive
particles are substantially uniformly interspersed throughout said
filament.
20. The abrasive brush according to claim 15, wherein said securing
element comprises a cylindrical hub, and wherein said filaments are
bonded to said hub.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of priority to U.S.
Provisional Application No. 60/917,172, entitled "EXTRUDED ABRASIVE
FILAMENT AND BRUSH" filed on May 10, 2007, the disclosure of which
is incorporated herein by reference.
FIELD
[0002] This disclosure relates to abrasive articles, more
specifically to abrasive filaments, articles containing abrasive
filaments and methods of using the same.
BACKGROUND
[0003] Polyamide, (nylon), filaments have been utilized since the
1950's as an alternative to natural filaments. An extrusion process
was developed for dispersing abrasive particles uniformly in a
nylon matrix in the form of a filament (U.S. Pat. Nos. 3,522,342
and 3,947,169). As polyamide filaments wear, new abrasive particles
are exposed. Brushes utilizing such filaments are therefore
considered to be regenerated during use.
[0004] Brushes incorporating abrasive bristles or filaments have
been used for many years to polish, clean and abrade a wide variety
of substrates. These brush products typically have a plurality of
bristles or filaments that contact the substrate during an abrading
process. The brushes are generally made by mixing abrasive
particles and any suitable thermoplastic binder together and then
extruding the composition to form a bristle or abrasive filament.
The abrasive filament is then cut to the desired length. A
plurality of these abrasive filaments are then mechanically or
adhesively combined to form a brush segment. A plurality of these
brush segments may be installed on a hub or plate to form a
brush.
[0005] Brushes including silicon carbide- or brown aluminum
oxide-loaded filaments are widely commercially available. However,
there is always a need for economical brushes having better
performance characteristics.
BRIEF SUMMARY
[0006] The present disclosure provides a method of deburring a
substrate having at least one burr, with a brush, the brush
comprising bristles comprising eutectic alumina zirconia particles
and a matrix of thermoplastic polymer, wherein the method comprises
the steps of: contacting the substrate with at least one bristle of
the brush in a contact region; and inducing relative motion between
the substrate and the at least one bristle.
[0007] The present disclosure also provides a method of refining a
substrate wherein the abrading efficiency exceeds 1.0.
[0008] The present disclosure also provides an abrasive filament
comprising: a matrix of thermoplastic polymer; and a plurality of
eutectic alumina zirconia particles interspersed throughout at
least a portion of the matrix wherein the refining efficiency
exceeds 1.0.
[0009] The present disclosure also provides an abrasive brush
comprising: a plurality of abrasive filaments, said filaments
comprising a matrix of thermoplastic polymer and a plurality of
eutectic alumina zirconia particles interspersed throughout at
least a portion of said matrix; and a securing element that
functions to secure the plurality of abrasive filaments to form a
brush wherein the refining efficiency exceeds 1.0.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a plan view of an exemplary brush as disclosed
herein;
[0011] FIG. 2 is a longitudinal cross sectional view of one
exemplary filament of the brush shown in FIG. 1;
[0012] FIG. 3a illustrates cut, wear, and efficiency data from
testing of various polyamide abrasive brushes on a perforated steel
plate;
[0013] FIG. 3b illustrates cut, wear, and efficiency data from
testing of various thermoplastic elastomer abrasive brushes on a
perforated steel plate;
[0014] FIG. 4a illustrates cut, wear, and efficiency data from
testing of various polyamide abrasive brushes on a steel plate;
[0015] FIG. 4b illustrates cut, wear, and efficiency data from
testing of various thermoplastic elastomer brushes on a steel
plate;
[0016] FIG. 5a illustrates cut, wear, and efficiency data from
testing of various polyamide abrasive brushes on an aluminum
plate;
[0017] FIG. 5b illustrates cut, wear, and efficiency data from
testing of various thermoplastic elastomer brushes on aluminum
plate;
[0018] FIG. 6a illustrates cut data from testing of various
polyamide abrasive brushes on a steel plate;
[0019] FIG. 6b illustrates cut data from testing of various
thermoplastic elastomer abrasive brushes on a steel plate;
[0020] FIG. 7a illustrates cut data from testing of various
polyamide abrasive brushes on an aluminum plate;
[0021] FIG. 7b illustrates cut data from testing of various
thermoplastic elastomer abrasive brushes on an aluminum plate;
[0022] FIG. 8a illustrates burr height data from testing of various
polyamide abrasive brushes on a perforated steel plate; and
[0023] FIG. 8b illustrates burr height data from testing of various
thermoplastic elastomer abrasive brushes on a perforated steel
plate.
[0024] These figures, which are idealized, are intended to be
merely illustrative of the abrasive article of the present
disclosure and non-limiting.
DETAILED DESCRIPTION
[0025] It is to be understood that embodiments beyond what are
mentioned here are contemplated and may be made without departing
from the scope or spirit of the present disclosure. The following
detailed description, therefore, is not to be taken in a limiting
sense.
[0026] All scientific and technical terms used herein have meanings
commonly used in the art unless otherwise specified. The
definitions provided herein are to facilitate understanding of
certain terms used frequently herein and are not meant to limit the
scope of the present disclosure.
[0027] Unless otherwise indicated, all numbers expressing feature
sizes, amounts, and physical properties used in the specification
and claims are to be understood as being modified in all instances
by the term "about." Accordingly, unless indicated to the contrary,
the numerical parameters set forth in the foregoing specification
and attached claims are approximations that can vary depending upon
the desired properties sought to be obtained by those skilled in
the art utilizing the teachings disclosed herein.
[0028] The recitation of numerical ranges by endpoints includes all
numbers subsumed within that range (e.g. 1 to 5 includes 1, 1.5, 2,
2.75, 3, 3.80, 4, and 5) and any range within that range.
[0029] As used in this specification and the appended claims, the
singular forms "a", "an", and "the" encompass embodiments having
plural referents, unless the content clearly dictates otherwise. As
used in this specification and the appended claims, the term "or"
is generally employed in its sense including "and/or" unless the
content clearly dictates otherwise.
[0030] Disclosed herein is an abrasive filament. The first type of
abrasive filaments include a thermoplastic matrix with abrasive
particles nearly uniformly interspersed in the matrix. In one
embodiment, the abrasive particles are substantially uniformly
interspersed throughout the thermoplastic matrix. This first type
of filament results in a substantially homogeneous abrasive
filament. The other type, of which there are numerous sub-types
include a sheath and a core, wherein the sheath and core are
generally made from different materials. Such filaments are
disclosed in U.S. Pat. No. 5,427,595, "Abrasive Filaments
Comprising Abrasive-Filled Thermoplastic Elastomer, Method of
Making Same, Articles Incorporating Same and Methods of Using Said
Articles," (Pihl et al.); in U.S. Pat. No. 5,460,883, "Composite
Abrasive Filaments, Methods of Making Same, Articles Incorporating
Same, and Methods of Using Said Articles," (Barber, Jr., et al);
and in U.S. Pat. No. 6,352,471, "Abrasive Brush with Filaments
Having Plastic Abrasive Particles Therein," (Bange et al.), the
entire disclosures of which are incorporated herein by
reference.
[0031] As used herein, the term "interspersed" means that the
abrasive particles are embedded within and located throughout the
thermoplastic material that forms the filament. In the case of the
core/sheath embodiments, "interspersed" means that the abrasive
particles are embedded within and located throughout the
thermoplastic matrix that forms the core or sheath, or both, as
appropriate. The particles are interspersed so as to create a
substantially homogenous distribution, though not necessarily an
absolutely homogenous distribution. Furthermore, while the majority
of the particles are wholly embedded within the thermoplastic
matrix, there may be some exposed particles at the surface that
extend partially outside of the thermoplastic matrix.
[0032] In one embodiment, an abrasive filament as described herein
can have an aspect ratio of at least about 1. In an embodiment, the
aspect ratio can be at least about 5. In an embodiment, the aspect
ratio can be at least about 10. In an embodiment, the aspect ratio
can be at least about 20. The aspect ratio is defined as the length
divided by the arithmetic average width. The filaments can be of
any length or width desired, and the cross-sectional shape can be
for example, round, oval, square, triangular, rectangular,
polygonal, or multilobal (such as trilobal, tetralobal, and the
like) in cross-section. Additionally, the abrasive filaments may
have a variable cross sectional area. For example, the filaments
can be "wavy" or textured. Likewise, the filaments can be
tapered.
[0033] The diameter of the abrasive filaments can generally range
from about 0.01 to 100 mm. In an embodiment the diameter can range
from about 0.05 mm to 50 mm. In an embodiment the diameter can
range from about 0.1 mm to 25 mm. In an embodiment the diameter can
range from about 0.2 mm to 10 mm. In an embodiment the diameter can
range from about 0.25 mm to 5 mm. The length of the filament, or
trim length, can range from about 1 to 1000 millimeters. In an
embodiment the length of the filament can range from about 2 to 100
mm. In an embodiment the length of the filament can range from
about 3 to 75 mm. In an embodiment the length of the filament can
range from about 4 to 50 mm. In an embodiment the length of the
filament can range from about 5 to 50 mm.
[0034] Abrasive filaments as disclosed herein include a
thermoplastic matrix and a plurality of abrasive particles. As used
herein, "thermoplastic matrix" refers to a material that is capable
of being heated to a molten state and then subsequently cooled to a
solid state. The thermoplastic matrix can be any thermoplastic
polymer or thermoplastic elastomer. Examples of particular
materials that can be used as the thermoplastic matrix include, but
are not limited to, polyamides, such as Nylon 6,12; and Hytrel.RTM.
thermoplastic elastomers.
[0035] Abrasive filaments as described herein also include abrasive
particles. The abrasive particles typically have a particle size
ranging from about 0.01 to 1000 micrometers, usually between about
1 to 150 micrometers. In one embodiment the abrasive particles have
a Mohs hardness of at least about 7. In an embodiment, the abrasive
particles have a Mohs hardness of at least about 9. Examples of
such abrasive particles include, but are not limited to, fused
aluminum oxide, ceramic aluminum oxide, boron carbide, titanium
diboride, heated treated aluminum oxide, silicon carbide, alumina
zirconia, diamond, ceria, cubic boron nitride, garnet and
combinations thereof.
[0036] In an embodiment, an abrasive filament as described herein
includes eutectic alumina zirconia abrasive particles. A eutectic
or eutectic mixture is a mixture of two or more phases at a
composition that has the lowest melting point, and where the phases
simultaneously crystallize from molten solution at this
temperature. Eutectic alumina zirconia can be produced by melting
alumina, baddeleyite (Zr0.sub.2), and other additives in an
electric arc furnace. The molten product is cooled down rapidly on
special cooling aggregates in order to obtain a microcrystalline
and homogeneous crystal structure. Eutectic alumina zirconia is
commercially available from, for example, Triebacher Schleifmittel
(Villach, Austria).
[0037] In one embodiment, the eutectic alumina zirconia particles
have an angular grain shape. In an embodiment, the eutectic alumina
zirconia particles include from about 50 to 60 percent by weight of
alumina. In an embodiment, the eutectic alumina zirconia particles
include from about 52 to 56 percent by weight of alumina. In an
embodiment, the eutectic alumina zirconia particles include from
about 54 to 55 percent by weight of alumina. In an embodiment, the
eutectic alumina zirconia particles include about 54.5 percent by
weight of alumina. In an embodiment, the eutectic alumina zirconia
particles include from about 35 to 45 percent by weight of
zirconia. In an embodiment, the eutectic alumina zirconia particles
include from about 40 to 43 percent by weight of zirconia. In an
embodiment, the eutectic alumina zirconia particles include from
about 41 to 42 percent by weight of zirconia. In an embodiment, the
eutectic alumina zirconia particles include about 41.5 percent by
weight of zirconia.
[0038] In an embodiment, eutectic alumina zirconia particles can
also include other compounds. In an embodiment, the eutectic
alumina zirconia particles include titanium dioxide (TiO.sub.2) and
iron oxide (Fe.sub.2O.sub.3). In an embodiment, the eutectic
alumina zirconia particles contain from about 2 to 3 percent by
weight TiO.sub.2; in another embodiment about 2.5 percent by weight
TiO.sub.2. In an embodiment, the eutectic alumina zirconia
particles contains from about 0.1 to 0.5 percent by weight
Fe.sub.2O.sub.3; in another embodiment about 0.2 percent by weight
Fe.sub.2O.sub.3.
[0039] Abrasive filaments as disclosed herein can include abrasive
particles of any size. In one embodiment, abrasive filaments can
include abrasive particles having a grain size from P16 Grit to
P400 Grit, using the FEPA test method. In an embodiment, abrasive
filaments include abrasive particles having a grain size (FEPA) of
P16, P20, P24, P30, P36, P40, P50, P60, P80, P100, P120, P150,
P180, P220, etc.
[0040] In an embodiment, the abrasive filament include from about
10 to 90 percent by weight of thermoplastic matrix, such as
polyamide or thermoplastic elastomer. In an embodiment, the
abrasive filament includes from about 50 to 80 percent by weight of
thermoplastic matrix, such as polyamide or thermoplastic elastomer.
In an embodiment, the abrasive filament includes from about 55 to
75 percent by weight of thermoplastic matrix, such as polyamide or
thermoplastic elastomer. In an embodiment, the abrasive filament
includes from about 10 to 90 percent by weight of abrasive
particles, such as eutectic alumina zirconia particles. In an
embodiment, the abrasive filament includes from about 20 to 50
percent by weight of abrasive particles, such as eutectic alumina
zirconia particles. In an embodiment, the abrasive filament
includes from about 25 to 45 percent by weight of abrasive
particles, such as eutectic alumina zirconia particles.
[0041] Additives may also be added to the abrasive filaments during
manufacture. Additives such as lubricants, soaps, antioxidants, UV
stabilizers, dye, pigments, wetting agents, surfactants,
plasticizers, anti-static agents, anti-rust agents, and other
liquid materials may be added to the filaments. One method of
incorporating these types of materials into the thermoplastic
matrix is to encapsulate the liquid materials into a shell that is
able to withstand the extrusion temperatures. Such methods are
generally well known in the art. The amounts of these materials
would generally be selected to provide desired properties as would
be known to those of skill in the art.
[0042] Abrasive filaments can also optionally include other
additives, such as, for example, fillers (including grinding aids),
fibers, antistatic agents, lubricants, wetting agents, surfactants,
pigments, dyes, coupling agents, anti-rust agents, plasticizers,
and suspending agents, Such additives can be blended directly into
the thermoplastic matrix or can be added by other methods known to
those of skill in the art. The amounts of these materials would
generally be selected to provide desired properties as would be
known to those of skill in the art.
[0043] Inorganic based particulate fillers can also be incorporated
along with the abrasive particles. Examples of useful fillers
include but are not limited to metal carbonates (such as calcium
carbonate (chalk, calcite, marl, travertine, marble and limestone),
calcium magnesium carbonate, sodium carbonate, magnesium
carbonate), silica (such as quartz, glass beads, glass bubbles and
glass fibers), silicates (such as talc, clays (montmorillonite),
feldspar, mica, calcium silicate, calcium metasilicate, sodium
aluminosilicate, sodium silicate), metal sulfates (such as calcium
sulfate, barium sulfate, sodium sulfate, aluminum sodium sulfate,
aluminum sulfate), gypsum, vermiculite, wood flour, aluminum
trihydrate, carbon black, metal oxides (such as calcium oxide
(lime), aluminum oxide, titanium dioxide), and metal sulfites (such
as calcium sulfite).
[0044] A grinding aid is defined as particulate material that the
addition of which has a significant effect on the chemical and
physical processes of abrading which results in improved
performance. In particular, it is believed that the grinding aid
will either 1) decrease the friction between the abrasive grains
and the workpiece being abraded, 2) prevent the abrasive grain from
"capping", i.e. prevent metal particles from becoming welded to the
tops of the abrasive grains, 3) decrease the interface temperature
between the abrasive grains the workpiece or 4) decrease the
grinding forces. In general, the addition of a grinding aid
increases the useful life of the abrasive filament. Grinding aids
encompass a wide variety of different materials and can be
inorganic or organic based. Examples of chemical groups of grinding
aids include waxes, organic halide compounds, halide salts and
metals and their alloys. The organic halide compounds will
typically break down during abrading and release a halogen acid or
a gaseous halide compound. Examples of such materials include but
are not limited to chlorinated waxes like tetrachloronaphtalene,
pentachloronaphthalene; and polyvinyl chloride. Examples of halide
salts include but are not limited to sodium chloride, potassium
cryolite, sodium cryolite, ammonium cryolite, potassium
tetrafluoroboate, sodium tetrafluoroborate, silicon fluorides,
potassium chloride, magnesium chloride. Examples of metals include,
but are not limited to, tin, lead, bismuth, cobalt, antimony,
cadmium, iron titanium. Other miscellaneous grinding aids include
sulfur, organic sulfur compounds, graphite and metallic
sulfides.
[0045] Examples of antistatic agents include, but are not limited
to, graphite, carbon black, vanadium oxide, humectants, and the
like.
[0046] The filament may also optionally include a toughening
material. Examples of such toughening materials include, but are
not limited to, rubber type polymers and plasticizers. Specific
examples of toughening materials include toluene sulfonamide
derivatives, styrene butadiene copolymers, polyether backbone
polyamide (commercially available from Arkema, Inc., under the
trade designation PEBAX), rubber grafted onto polyamide
(commercially available from duPont under the trade designation
"ZYTEL FN") and a triblock polymer of styrene-(ethylene
butylene)-styrene (commercially available from Kraton Polymers LLC,
under the trade designation "KRATON 1901 X").
[0047] Abrasive filaments as described herein may be incorporated
into a wide variety of brushes, either assembled to form an open,
lofty abrasive pad, or attached to various substrates. Abrasive
brushes, as disclosed herein include a plurality of abrasive
filaments as disclosed herein, and a securing element. Generally,
the securing element functions to secure the plurality of abrasive
filaments to form a brush.
[0048] The filaments disclosed herein can be incorporated into
brushes of many types and for myriad uses, such as cleaning,
deburring, radiusing, imparting decorative finishes onto metal,
plastic, and glass substrates, and like uses. Brush types include
wheel brushes, cylinder brushes (such as printed circuit cleaning
brushes), mini-grinder brushes, floor scrubbing brushes, cup
brushes, end brushes, flared cup end brushes, circular flared end
cup brushes, coated cup and variable trim end brushes, encapsulated
end brushes, pilot bonding brushes, tube brushes of various shapes,
coil spring brushes, flue cleaning brushes, chimney and duct
brushes, and the like. The filaments in any one brush can of course
be the same or different. A non-limiting list of exemplary brushes
in which the abrasive filaments described herein can be used
include brushes such as those described in U.S. Pat. Nos.
5,016,311, 5,083,840, and 5,233,719 (Young et al.), and U.S. Pat.
No. 5,400,458 (Rambosek), the disclosures of which are incorporated
herein by reference.
[0049] In general, one such brush construction has a securing
element that includes a base layer, and a binder layer. The
abrasive filaments, or bristles are individually and uniformly
embedded in the binder layer such that they project upward and are
generally parallel to one another. The base layer and the binder
layer can be the same material or different materials and in
general these layers are polymeric materials. For example the base
layer can be a flexible resilient polymeric open cell foam, a
polyester material or a polyamide material. In addition, a cotton,
polyamide or polyester fabric can be incorporated into these
polymeric materials. The binder layer is usually a semi-rigid
polymeric material such as a polyurethane, polyester, epoxy or
polyamide. In an embodiment where the base layer and the binder
layer are the same, they can be made of a polyurethane material. In
general the thickness of the base layer and binder layers can range
between about 1 to 10 millimeters. In another embodiment, from
about 2 to 5 millimeters. The larger the diameter of the bristles,
the thicker the binder layer is. An abrasive brush that includes an
abrasive filament as described herein can be mounted via the
securing element to an apparatus capable of inducing relative
motion between a substrate and at least one of the abrasive
filaments.
[0050] An abrasive brush can include only abrasive filaments
described herein. Alternatively, an abrasive brush can comprise a
mixture of abrasive filaments described herein and polymeric
filaments. Such polymeric filaments include those without abrasive
particles, and those including abrasive particles.
[0051] The polymeric filaments can include filaments made of, for
example, polyamide, polypropylene, polyester, thermoplastic
elastomer and polyethylene. In some cases the filaments can be
hollow, which is well known in the brush art. In addition the
polymeric filaments may contain abrasive particles such as those
well known in the art like silicon carbide and aluminum oxide. The
particle size of these abrasive particles will vary depending upon
the application, but in general they can range from about 10 to
1000 micrometers. In another embodiment from about 15 to 120
micrometers.
[0052] In some brushes the filaments will be nearly perpendicular
to the binder layer, in other applications such as conveyor
systems, the filaments will be placed at a specified angle or a
specified tilt.
[0053] In another embodiment a bristle having abrasive particles
with materials encapsulated therein are included. Examples of
encapsulated materials can include soaps, lubricants, anti-rust
agents, and anti-static agents. In an embodiment, phosphoric acid
(or a similar material) can be added to a bristle comprising
abrasive particles. A brush made with such bristles would be useful
in the removal and/or neutralization of surface rust on articles
such as, for example, automobiles, benches, and swingsets.
[0054] One embodiment as described herein can include a unitary
injection molded abrasive brush. Such molded brushes can be made as
described in co-pending U.S. Pat. No. 5,679,067, "Molded Abrasive
Brush," (Johnson et al.), the entire disclosure of which is
incorporated herein by reference. In such a brush, a securing
element can include a threaded stud. The bristles can have an
aspect ratio of at least about 2 and can be integrally molded with
the base. The molded abrasive brush comprises a thermoplastic
matrix having abrasive particles interspersed throughout at least
the bristles. The bristles extend generally perpendicular to the
base layer, parallel to the axis of rotation of the molded abrasive
brush.
[0055] Another example of a unitary injection molded brush can be
made as is disclosed in U.S. Pat. No. 5,903,951, "Radial Brush
Segment," (lonta et al.), the entire disclosure of which is
incorporated herein by reference. The brush segment can be molded
from a thermoplastic matrix having a plurality of abrasive
particles interspersed throughout at least the bristles. The molded
brush segments can be generally circular, with the bristles
extending radially outward in the plane defined by the central
portion. A plurality of brush segments can be combined to form a
brush assembly.
[0056] FIGS. 1 and 2 show an exemplary embodiment of a unitary
injection molded brush. Such a brush includes molded brush segment
210 having a plurality of integrally molded filaments or bristles
218 extending from the outer edge 214 of the securing element 212.
The securing element 212 in this exemplary embodiment is shown as a
cylindrical hub. Securing element 212 functions to secure the
plurality of molded filaments 218 together to form a brush segment.
Each filament includes a matrix 228 having a plurality of abrasive
particles 226, such as eutectic alumina zirconia particles
interspersed throughout at least the bristles (the matrix 228 and
particles 226 are illustrated in FIG. 2 which depicts an exemplary
filament 218). The molded brush segments can be generally circular,
with the bristles extending radially outward in the plane defined
by the securing element 212. A plurality of brush segments can be
combined to form a brush. FIG. 1 illustrates the brush segment 210
in contact with a workpiece 100 at the contact region 102.
[0057] In one embodiment, the securing element includes a
cylindrical hub. Generally, the abrasive filaments are bonded to
the cylindrical hub. One of skill in the art would know, having
read this specification, how to manufacture such an abrasive
brush.
[0058] The workpiece can be any type of material such as metal,
metal alloys, exotic metal alloys, ceramics, glass, wood, wood like
materials, composites, painted surface, plastics, reinforced
plastic, stones, and combinations thereof. The workpiece may also
contain an unwanted layer or coating external over the workpiece
surface. This coating may be for example paint, dirt, debris, oil,
oxide coating, rust, adhesive, gasket material and the like. The
workpiece may be flat or may have a shape or contour associated
with it.
[0059] In an embodiment, the workpiece is aluminum. In one
embodiment, the workpiece has at least one burr. A workpiece that
includes at least one burr can generally be a perforated piece. In
one embodiment, the workpiece is carbon steel.
[0060] Depending upon the application, the force at the abrading
interface or contact region can range from about 0.98 N to over 980
N. Generally this range is between about 9.8 N to 490 N of force at
the abrading interface. Also depending upon the application, there
may be a liquid present during abrading. This liquid can be water,
an organic compound, a mixture comprising water and oil, or
combinations thereof. Examples of typical organic compounds include
lubricants, oils, emulsified organic compounds, cutting fluids,
soaps, or the like. These liquids may also contain other additives
such as defoamers, degreasers, corrosion inhibitors, or the like.
The abrasive article may oscillate at the abrading interface during
use. In some instances, this oscillation may result in a finer
surface on the workpiece being abraded.
[0061] The brush as disclosed herein can be used by hand or used in
combination with a machine to refine a surface by: cleaning a
workpiece surface, including removing paint or other coatings,
gasket material, corrosion, or other foreign material. At least one
or both of the brush and the workpiece can be moved relative to the
other. The abrasive article or brush can be converted into a belt,
tape rolls, disc, sheet, and the like. Typically brush discs can be
secured to a back-up pad by an attachment means. These brush discs
can rotate between about 100 to 30,000 revolutions per minute,
typically between about 500 to 20,000 revolutions per minute.
[0062] An abrasive brush as disclosed herein can be used to deburr
a substrate. Methods of deburring a substrate generally include
contacting the substrate with at least one bristle of an abrasive
brush as described herein in a contact region; and inducing
relative motion between the substrate and the at least one bristle.
A method of deburring can also optionally include applying a
lubricant adjacent the contact region.
[0063] An abrasive brush as disclosed herein can also be used to
refine a surface of a substrate. Methods of refining the surface of
a substrate generally include contacting the substrate with at
least one bristle of an abrasive brush as described herein in a
contact region; and inducing relative motion between the substrate
and the at least one bristle, wherein the efficiency exceeds about
1.0.
[0064] In general, abrasive brushes, and methods of using abrasive
brushes can have associated brush efficiency or efficiencies,
respectively. For example, a method of abrading a substrate can
have an associated efficiency, and a method of refining a surface
of a substrate can have an associated efficiency. Brush efficiency,
or the efficiency of a method of using a brush (to deburr a
substrate or to refine a surface of a substrate, for example) is
generally the ratio of the mass of the substrate cut or abraded by
the brush in a time interval (for example, grams of substrate) to
the mass of the brush that is worn in that same time interval (for
example, grams of the brush). The amount of the brush that is worn
can be calculated by taking the difference in the brush weight
before and after the substrate is worked upon. In an embodiment, a
brush efficiency or an efficiency of a method of abrading a
substrate, or refining a surface of a substrate can have an
efficiency that is at least about 1 or greater. Greater magnitudes
of brush efficiency imply better brush performance.
[0065] In general, an abrasive filament as described herein can be
made by (a) rendering a thermoplastic matrix molten and combining
abrasive particles therewith; (b) extruding the molten
thermoplastic matrix and abrasive particles; and (c) cooling the
composition to a temperature sufficient to harden the molten
thermoplastic matrix and thus form a hardened composition
comprising a thermoplastic matrix having abrasive particles
interspersed throughout.
[0066] Methods of making abrasive filaments with sheaths and cores
include those disclosed is U.S. Pat. No. 6,352,471 (Bange et al.),
the disclosure of which is incorporated herein by reference, and
U.S. Pat. No. 5,460,885, Barber et al., and U.S. Pat. No.
5,427,595, Pihl et al., already incorporated by reference. The
methods and apparatuses for forming such filaments as given therein
can advantageously be modified as is within the knowledge of those
skilled in the art to extrude monofilament embodiments as disclosed
herein.
[0067] Abrasive filaments may also be made using unitary injection
molding. Such a method comprises the steps of: a) mixing a
thermoplastic matrix and plastic abrasive particles together to
form a mixture; b) heating the mixture to form a flowable material;
and c) injecting the flowable material under pressure into a mold
to form an abrasive brush, wherein the brush comprises a securing
element, such as a generally planar flexible base or center
portion, and a plurality of bristles extending from the base or
center portion, wherein the bristles are integrally molded with the
base.
[0068] Generally a single screw or a twin screw extruder can be
utilized. In addition, a CTM (cavity transfer mixer) can also be
used. These extruders are known in the art of thermoplastic
extrusion. Temperatures, material feed rates, hoppers, and the like
are also known.
[0069] The abrasive particles can be mixed with the thermoplastic
while the thermoplastic is either in the molten or solid state. A
single stream of polymer/plastic can be used to produce filaments
as disclosed herein. In an alternate method, two individual feed
streams can be used.
[0070] Abrasive particles may be added to the molten thermoplastic
matrix through a feed port in the extruder into the molten
thermoplastic matrix mass. In an embodiment, they can be added at a
point early enough to afford adequate dispersal of abrasive
particles throughout the molten thermoplastic matrix.
Alternatively, abrasive particles may be distributed in the molten
thermoplastic matrix coating via a second step (i.e. after the
preformed core has been coated with molten thermoplastic matrix),
such as by electrostatic coating.
[0071] Abrasive filaments as disclosed herein including a
thermoplastic matrix and abrasive particles can be extruded into
cross-sectional shapes such as circles, ovals, and ellipses,
polygons such as, for example, squares, rectangles, hexagons, and
trapezoids, stars, and any other shape.
[0072] A cold water quench can be located immediately downstream of
the die through which the molten extruded or coextruded filament or
the thermoplastic matrix coated preformed core passes to achieve
rapid cooling of the molten thermoplastic matrix to form a hardened
composition comprising thermoplastic matrix and abrasive
particles.
[0073] The abrasive filament may then be cut into individual
abrasive filaments having the desired length. Although it is within
the scope of this disclosure to orient the filaments to increase
their tensile strength prior to use, it is not necessary to do
so.
[0074] After the molten, abrasive filament has hardened, the
filaments may have a coating (e.g. a plastic coating) applied there
over. It is also within the scope of this disclosure to have the
abrasive particles protrude out of the filament.
[0075] Disclosed herein is a method of deburring a substrate having
at least one burr, with a brush, the brush comprising bristles
comprising eutectic alumina zirconia particles and a matrix of
thermoplastic polymer, wherein the method comprises the steps of:
contacting the substrate with at least one bristle of the brush in
a contact region; and inducing relative motion between the
substrate and the at least one bristle.
[0076] Also disclosed herein is the method discussed in the
preceding paragraph, wherein the eutectic alumina zirconia
particles comprise from about 50 to 60 percent by weight of
alumina. Also disclosed herein is the method discussed in the
preceding paragraph, wherein the eutectic alumina zirconia
particles comprise from about 52 to 56 percent by weight of
alumina. Also disclosed herein is the method discussed in the
preceding paragraph, wherein the eutectic alumina zirconia
particles comprise from about 38 to 43 percent by weight of
zirconia. Also disclosed herein is the method discussed in the
preceding paragraph, wherein the abrasive particles are
substantially uniformly interspersed throughout said filament. Also
disclosed herein is the method discussed in the preceding
paragraph, wherein the abrasive filament comprises about 10 percent
to 90 percent by weight of thermoplastic polymer; and about 10
percent to 90 percent by weight of eutectic alumina zirconia
particles. Also disclosed herein is the method discussed in the
preceding paragraph, wherein the abrasive filament comprises about
50 percent to 80 percent by weight of thermoplastic polymer; and
about 20 percent to 50 percent by weight of eutectic alumina
zirconia particles. Also disclosed herein is the method discussed
in the preceding paragraph, wherein the securing element comprises
a cylindrical hub, and wherein said filaments are bonded to said
hub.
[0077] Disclosed herein is a method of refining the surface of a
substrate with a brush, the brush comprising bristles comprising
eutectic alumina zirconia particles and a matrix of thermoplastic
polymer, wherein the method comprises the steps of: contacting the
substrate with at least one bristle of the brush in a contact
region; and inducing relative motion between the substrate and the
at least one bristle, wherein the efficiency is at least about
1.0.
[0078] Also disclosed herein is the method discussed in the
preceding paragraph, wherein the eutectic alumina zirconia
particles comprise from about 50 to about 60 percent by weight of
alumina. Also disclosed herein is the method discussed in the
preceding paragraph, wherein the eutectic alumina zirconia
particles comprise from about 52 to about 56 percent by weight of
alumina. Also disclosed herein is the method discussed in the
preceding paragraph, wherein the eutectic alumina zirconia
particles comprise from about 38 to 43 percent by weight of
zirconia. Also disclosed herein is the method discussed in the
preceding paragraph, wherein the abrasive filament comprises about
10 percent to about 90 percent by weight of thermoplastic polymer;
and about 10 percent to about 90 percent by weight of eutectic
alumina zirconia particles. Also disclosed herein is the method
discussed in the preceding paragraph, wherein the abrasive filament
comprises about 50 percent to about 80 percent by weight of
thermoplastic polymer; and about 20 percent to about 50 percent by
weight of eutectic alumina zirconia particles. Also disclosed
herein is the method discussed in the preceding paragraph, wherein
the securing element comprises a cylindrical hub, and wherein said
filaments are bonded to said hub.
[0079] Disclosed herein is an abrasive filament comprising: a
matrix of thermoplastic polymer; and a plurality of eutectic
alumina zirconia particles interspersed throughout at least a
portion of the matrix, wherein the efficiency of abrading a
workpiece is at least about 1.0.
[0080] Also disclosed herein is the abrasive filament discussed in
the preceding paragraph, wherein said matrix of thermoplastic
polymer comprises a polymer selected from polyamide and
thermoplastic elastomer. Also disclosed herein is the abrasive
filament discussed in the preceding paragraph, wherein the eutectic
alumina zirconia particles comprise from about 50 to about 60
percent by weight of alumina. Also disclosed herein is the abrasive
filament discussed in the preceding paragraph, wherein the eutectic
alumina zirconia particles comprise from about 52 to about 56
percent by weight of alumina. Also disclosed herein is the abrasive
filament discussed in the preceding paragraph, wherein the eutectic
alumina zirconia particles comprise from about 35 to 45 percent by
weight of zirconia. Also disclosed herein is the abrasive filament
discussed in the preceding paragraph, wherein the eutectic alumina
zirconia particles comprise from about 38 to 43 percent by weight
of zirconia. Also disclosed herein is the abrasive filament
discussed in the preceding paragraph, wherein said abrasive
filament comprises about 10 percent to about 90 percent by weight
of thermoplastic polymer; and about 10 percent to about 90 percent
by weight of eutectic alumina zirconia particles. Also disclosed
herein is the abrasive filament discussed in the preceding
paragraph, wherein said abrasive filament comprises about 50
percent to about 80 percent by weight of thermoplastic polymer; and
about 20 percent to about 50 percent by weight of eutectic alumina
zirconia particles. Also disclosed herein is the abrasive filament
discussed in the preceding paragraph, wherein said abrasive
filament comprises about 55 percent to about 75 percent by weight
of thermoplastic polymer; and about 25 percent to about 45 percent
by weight of eutectic alumina zirconia particles. Also disclosed
herein is the abrasive filament discussed in the preceding
paragraph, wherein said abrasive particles are substantially
uniformly interspersed throughout said filament.
[0081] Disclosed herein is an abrasive brush comprising: a
plurality of abrasive filaments, said filaments comprising a matrix
of thermoplastic polymer and a plurality of eutectic alumina
zirconia particles interspersed throughout at least a portion of
said matrix; and a securing element that functions to secure the
plurality of abrasive filaments to form a brush, wherein the
abrading efficiency on a workpiece is at least about 1.0.
[0082] Also disclosed herein is the abrasive brush discussed in the
preceding paragraph, wherein the eutectic alumina zirconia
particles comprise from about 50 to about 60 percent by weight of
alumina. Also disclosed herein is the abrasive brush discussed in
the preceding paragraph, wherein the eutectic alumina zirconia
particles comprise from about 52 to about 56 percent by weight of
alumina. Also disclosed herein is the abrasive brush discussed in
the preceding paragraph, wherein the eutectic alumina zirconia
particles comprise from about 38 to 43 percent by weight of
zirconia. Also disclosed herein is the abrasive brush discussed in
the preceding paragraph, wherein said abrasive filament comprises
about 10 percent to about 90 percent by weight of thermoplastic
polymer; and about 10 percent to about 90 percent by weight of
eutectic alumina zirconia particles. Also disclosed herein is the
abrasive brush discussed in the preceding paragraph, wherein said
abrasive filament comprises about 50 percent to about 80 percent by
weight of thermoplastic polymer; and about 20 percent to about 50
percent by weight of eutectic alumina zirconia particles. Also
disclosed herein is the abrasive brush discussed in the preceding
paragraph, comprising a plurality of abrasive filaments as
discussed above. Also disclosed herein is the abrasive brush
discussed in the preceding paragraph further comprising a securing
element that functions to secure the plurality of abrasive
filaments to form a brush. Also disclosed herein is the abrasive
brush discussed in the preceding paragraph, wherein said securing
element comprises a cylindrical hub, and wherein said abrasive
filaments are bonded to said hub.
WORKING EXAMPLES
[0083] The disclosure will now be further added to with reference
to the following examples. These examples demonstrate various
specific embodiments and are not intended to limit the scope of
this disclosure.
Example 1
Manufacture of Filaments and Brushes
[0084] Abrasive filled filaments were made using a Werner-Pfleider
twin screw extruder. The filaments were nominally 0.71 mm (0.028
inch) diameter and used polyamide ("ZYTEL 158 NC010" nylon 6,12
resin (E.I. DuPont de Nemours & Co., Wilmington, Del.) or a
compound of thermoplastic elastomer "HYTREL 6356 polyester TPE
resin (E.I. DuPont de Nemours & Co., Wilmington, Del.) and
lubricant "MB50-010" (MultiBase, Copley, Ohio) as the matrix.
Pellets of Hytrel 6356 and MB50-010 were mechanically mixed to
attain a homogeneous mixture; this mixture was fed into the feed
port of the extruder. The abrasive mineral was introduced into the
molten polymer via a vent port in the extruder using a gravimetric
feeder to maintain correct resin:mineral weight ratios. In order to
achieve similar volume ratios of mineral to thermoplastic matrix,
mineral addition weights were adjusted to accommodate differences
in density between aluminum oxide and silicon carbide and
alumina-zirconia eutectic mineral. The filaments that were made are
shown below in Table 1.
TABLE-US-00001 TABLE 1 Mineral Weight Mineral % in Matrix Mineral
Grade Manufacturer Filament Nylon 6,12 Brown Aluminum ANSI120
Washington 30 Oxide Mills, Niagra Falls, NY Nylon 6,12 Black
Silicon P120 UK Abrasives 24.3 Carbide Inc., Northbrook, IL Nylon
6,12 ZK40 - Alumina- NP120 Triebacher 36.6 Zirconia Schleifmittel,
Eutectic Villach, Austria TPE Brown Aluminum ANSI120 Washington 30
Oxide Mills, Niagra Falls, NY TPE Black Silicon P120 UK Abrasives
24.3 Carbide Inc., Northbrook, IL TPE ZK40 - Alumina- NP120
Triebacher 36.6 Zirconia Schleifmittel, Eutectic Villach,
Austria
[0085] The filaments were converted into 8 inch nominal OD.times.2
inch ID.times.1 inch wide (20.32.times.5.08.times.2.54 cm) brushes
(Tanis Inc., Delafield, Wis.). The brushes were made with nominal
2.54 and 5.08 cm (1 inch and 2 inch) trim lengths. A constant fiber
density was maintained between brushes of the same trim length. A
single brush was constructed with each filament type.
Example 2
Cut, Wear and Efficiency Testing
[0086] Tests were conducted by running the brushes at 1750 rpm and
placing them in contact with a test substrate for 150 seconds,
followed by cooling for 30 seconds, and repeating for two more
cycles under a load of 22.24 N (5 lbf). The test substrate was
moved at a speed of 7.62 cm/sec (3 inch/second) up and down over a
distance of 17.78 cm (7 inches) during the test. Brush cut and wear
were calculated as the change in test substrate weight and brush
weight before and after the test, respectively. The performance of
the brushes was measured by "brush efficiency", which was
calculated by determining the mass of substrate abraded away by the
brush in a time interval divided by the mass of the brush lost in
that same time interval. Greater magnitudes of brush efficiency
connote better brush performance.
[0087] The 2 inch (5.08 cm) trim brushes were run against the burr
side of perforated cold roll steel plate to replicate deburring
operations (FIGS. 3a and 3b). The 1 inch (2.54 cm) trim brushes
were run against 1008 cold roll steel plate (FIGS. 4a and 4b) and
6061 T6 aluminum plate (FIGS. 5a and 5b) to replicate
finishing/cleaning operations. FIGS. 3a-5b show the results of this
testing. Note that the second data set of a brush is the second
consecutive run of the product. The 1 inch (2.54 cm) trim brushes
were first run on the carbon steel plate (twice) and then on the
aluminum plate (twice).
[0088] As seen in FIGS. 3a-5b, the brush made with ZK40
outperformed brown aluminum oxide (BAO) and silicon carbide (SiC)
on all three surfaces.
Example 3
Extended Cut Testing
[0089] A test "run" was conducted by running the brushes at 1750
rpm and placing them in contact with a test substrate (carbon steel
or aluminum) for 150 seconds, followed by cooling for 30 seconds,
and repeating for two more cycles under a load of 22.24 N (5 lbf).
The test substrate was moved at a speed of 7.62 cm/sec (3
inch/second) up and down over a distance of 17.78 cm (7 inches)
during the test. Brush cut was calculated as the change in test
substrate weight before and after the test. The test run was
repeated consecutively four more times.
[0090] 2.54 cm (1 inch) trim brushes (manufactured as in Example 1)
were run against a 1008 cold rolled steel plate (FIGS. 6a and 6b)
and a 6061 T6 aluminum plate (FIGS. 7a and 7b) to replicate
finishing/cleaning operations. The 1 inch (2.54 cm) trim brushes
were first run on the carbon steel plate and then on the aluminum.
As seen in FIGS. 6a, 6b, 7a and 7b, the brushes that included ZK 40
had comparable or better results on both carbon steel and
aluminum.
Example 4
Deburring Testing
[0091] Filaments were converted into brushes for testing as
discussed in Example 1. Test brushes were mounted on an arbor with
a means for rotating them to 1750 rpm. The burr side (the
perforating die exit side) of a metal workpiece consisting of a 50
mm.times.280 mm piece of 16 gauge (1.5189 mm thick) 1008 CRS
perforated screen (4 mm diameter staggered holes, 46% open, stock
pattern number 041, commercially available from Harrington &
King Perforating Company, Chicago, Ill.) was urged against the
rotating brush in each case with a force of 22.2 N. The test metal
perforated screen was moved up at the rate of 76 mm/second
traversing a stroke of 178 mm. At the end of the stroke, the
perforated screen was separated from the brush, moved back to its
original position, and re-engaged with the brush for another
stroke. This was repeated for a total of 3 strokes. The perforated
screen was rotated 180 degrees in-plane (to simulate a
"downstroke") and another 3 strokes were completed, thereby
providing a test specimen that had been deburred 3 upstrokes and 3
downstrokes (3U3D). Two additional perforated screens were deburred
with each test brush, one 6U6D and the other 8U8D.
[0092] The height of residual burrs following deburring was
measured on a centrally-disposed hole in each test screen by
vertical scanning interferometry using a WYCO NT9800 Optical
Profiling System (Veeco Instruments Inc., Woodbury, N.Y.) set at 2%
modulation threshold with a 10.times. objective and a 0.5.times.
transfer lens producing a unified image via stitching mode.
Measurements were made at eight locations spaced at 45 degrees
around each hole. The results are shown in Table 2 below and
graphically in FIGS. 8a and 8b and show that for the brushes made
with polyamide (Nylon 6,12) the burr height was reduced by 42% for
brushes containing brown aluminum oxide-containing filaments, 56%
for brushes containing silicon carbide-containing filaments, and
80% for brushes containing ZK 40-containing filaments. The
deburring tests done with brushes having a TPE matrix (Hytrel 6356)
should be qualified by the following factors: the burr heights were
smaller to begin with (Table 2 residual burr height at 0 brushing
strokes); and the TPE matrix wears faster than the polyamide so the
cutting faces are being regenerated more often; the result being
that under the test conditions used the TPE brushes remove the
burrs at a faster rate than the polyamide brushes. These factors
make a direct comparison of the polyamide and TPE matrix brushes
with the burr height data difficult. However, using cut, wear and
efficiency data, comparison of FIGS. 1a to 1b shows that TPE matrix
brushes are more efficient at burr removal on carbon steel than
polyamide brushes under the test conditions used. Deburring tests
were carried out on perforated aluminum and showed similar
results.
TABLE-US-00002 TABLE 2 Residual burr height (micrometers) Nylon
6,12 Hytrel TPE Brushing Strokes BAO SiC ZK40 BAO SiC ZK40 0 45.2
45.2 45.2 32.1 32.1 32.1 3U3D 32.9625 27.5125 15.725 8 5.2 5.2 6U6D
37.8 19.6625 12.525 5.2 6.1 5.2 8U8D 26.825 20.175 9.3625 5.2 5.2
3.2
[0093] Thus, embodiments of extruded abrasive filaments and brushes
formed thereby are disclosed. One skilled in the art will
appreciate that the subject matter of this disclosure can be
practiced with embodiments other than those disclosed. The
disclosed embodiments are presented for purposes of illustration
and not limitation, and this disclosure is limited only by the
claims that follow.
* * * * *