U.S. patent application number 13/836734 was filed with the patent office on 2014-07-03 for lower melting point binder metals.
This patent application is currently assigned to SMITH INTERNATIONAL, INC.. The applicant listed for this patent is SMITH INTERNATIONAL, INC.. Invention is credited to MINGDONG CAI, GREGORY LOCKWOOD.
Application Number | 20140182948 13/836734 |
Document ID | / |
Family ID | 51015884 |
Filed Date | 2014-07-03 |
United States Patent
Application |
20140182948 |
Kind Code |
A1 |
CAI; MINGDONG ; et
al. |
July 3, 2014 |
LOWER MELTING POINT BINDER METALS
Abstract
A copper, manganese, nickel, zinc and tin binder metal
composition having a melting point of 1500.degree. F. or less that
includes zinc and tin at a sum weight of about 26.5% to about 30.5%
in which zinc is at least about 12% and Sn is at least about 6.5%.
The binder metal having a melting point of 1500.degree. F. or less
can be used at an infiltrating temperature of 1800.degree. F. or
less in forming drilling tools and tool components.
Inventors: |
CAI; MINGDONG; (HOUSTON,
TX) ; LOCKWOOD; GREGORY; (PEARLAND, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SMITH INTERNATIONAL, INC. |
HOUSTON |
TX |
US |
|
|
Assignee: |
SMITH INTERNATIONAL, INC.
HOUSTON
TX
|
Family ID: |
51015884 |
Appl. No.: |
13/836734 |
Filed: |
March 15, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61748045 |
Dec 31, 2012 |
|
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|
Current U.S.
Class: |
175/425 ; 164/97;
420/473; 420/587 |
Current CPC
Class: |
B22F 7/062 20130101;
C22C 1/0425 20130101; C22C 9/02 20130101; C22C 29/08 20130101; B22F
2999/00 20130101; C22C 9/04 20130101; E21B 10/54 20130101; C22C
29/00 20130101; B22F 2303/35 20130101; C22C 30/02 20130101; B22F
2999/00 20130101; C22C 9/05 20130101 |
Class at
Publication: |
175/425 ;
420/587; 420/473; 164/97 |
International
Class: |
C22C 9/04 20060101
C22C009/04; C22C 9/05 20060101 C22C009/05; E21B 10/54 20060101
E21B010/54; C22C 30/02 20060101 C22C030/02 |
Claims
1. A binder metal composition having a melting point of
1500.degree. F. or less, the binder metal composition, comprising:
zinc (Zn) and tin (Sn) having a sum weight % of about 26.5% to
about 30.5% in which Zn is at least about 12% and Sn is at least
about 6.5%; nickel (Ni) at about 4.5 to about 6.5 weight %;
manganese (Mn) at about 11 to about 26 weight %; and copper (Cu) at
about 40 to about 55 weight %.
2. The binder metal composition of claim 1, wherein Mn is present
at about 14 to about 21 weight % and Cu is present at about 40 to
about 55 weight %.
3. The binder metal composition of claim 1, wherein Mn is present
at about 17 weight % and Cu is present at about 49 weight %.
4. The binder metal composition of claim 1, further comprising an
additive selected from the group consisting of boron, silicon, iron
cobalt, aluminum, titanium, niobium, molybdenum, tungsten and
combinations thereof.
5. An infiltrated metal-matrix composite comprising: hard matrix
particles which are infiltrated with the binder metal composition
of claim 1.
6. The infiltrated metal-matrix composite of claim 5, wherein the
infiltrated metal-matrix has a transverse rupture strength (TRS) of
90-140 ksi.
7. A drill bit body comprising a plurality of blades, the plurality
of blades comprising the infiltrated metal-matrix composite of
claim 5.
8. An infiltrated metal-matrix composite comprising the binder
metal composition of claim 1, wherein the infiltrated binder metal
has a mixture of a first face-centered cubic (FCC) phase and a
second FCC phase, and the first FCC phase has different chemistry
and lattice parameters than the second FCC phase.
9. The infiltrated metal-matrix composite of claim 8, wherein the
ratio of the first FCC phase to the second FCC phase is about 1 to
1.5:1.
10. A drill bit body comprising: hard matrix particles which are
infiltrated with the binder metal composition of claim 1.
11. A binder metal composition having a melting point of
1500.degree. F. or less, the binder metal composition, comprising:
Sn at about 6.5% to about 16 weight %; Zn at about 12 to about
22.75 weight %; Ni at about 4.5 to about 6.5 weight %; Mn at about
11 to about 26 weight %; and Cu at about 40 to about 55 weight
%.
12. The binder metal composition of claim 11, wherein Mn is present
at about 17 weight % and Cu is present at about 49 weight %.
13. The binder metal composition of claim 12, wherein Sn is present
at about 16 weight %; Zn is present at about 12 weight %, and Ni is
present at about 6 weight %.
14. The binder metal composition of claim 12, wherein Sn is present
at about 10 weight %, Zn is present at about 19 weight %, and Ni is
present at about 5 weight %.
15. The binder metal composition of claim 12, wherein Sn is present
at about 13 weight %, Zn is present at about 15.5 weight %, and Ni
is present at about 5.5 weight %.
16. The binder metal composition of claim 12, wherein Sn is present
at about 15 weight %, Zn is present at about 12.5 weight %, and Ni
is present at about 6.5 weight %.
17. The binder metal composition of claim 12, wherein Sn is present
at about 6.75 weight %, Zn is present at about 22.75 weight %, and
Ni is present at about 4.5 weight %.
18. A method of forming an infiltrated metal-matrix composite,
comprising: infiltrating tungsten carbide particles using a binder
metal, the binder metal comprising: zinc (Zn) and tin (Sn) having a
sum weight % of about 26.5% to about 30.5% in which Zn is at least
about 12% and Sn is at least about 6.5%; nickel (Ni) at about 4.5
to about 6.5 weight %; manganese (Mn) at about 11 to about 26
weight %; and copper (Cu) at about 40 to about 55 weight %.
19. The method of claim 18, wherein infiltrating comprises
infiltrating at a temperature of about 1800.degree. F. or less.
20. A binder metal composition having a melting point of
1500.degree. F. or less, the binder metal composition, comprising:
zinc (Zn) and tin (Sn) having a sum weight % of about 26.5% to
about 30.5% in which Zn is at least about 12% and Sn is at least
about 6.5%; nickel (Ni) at about 4.5 to about 6.5 weight %; and
copper (Cu) at about 51 to about 81 weight %.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims the benefit of U.S. Provisional
Patent Application Ser. No. 61/748,045 filed Dec. 31, 2012, which
is incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] This application is directed to a binder metal having a
melting point of 1500.degree. F. or less that includes at least Cu,
Ni, Zn and Sn and is used in the manufacturing of drilling
tools.
BACKGROUND
[0003] The manufacturing of drill bit bodies involves heating a
mixture of hard matrix particles (e.g., tungsten carbide) and a
binder metal which are placed in a bit body mold for approximately
75 to 205 minutes at 1875.degree. to 2100.degree. Fahrenheit (F)
causing infiltration of the binder metal through the hard matrix
particles. The infiltration process results in a metal-matrix
composite that forms the "bit body." The infiltration occurs when
the molten binder metal flows through spaces between the hard
matrix particle grains by means of capillary action. Upon cooling,
the hard matrix particles and the binder metal form a hard,
durable, strong metal-matrix composite. If the infiltration process
is not complete, the bit body is often defective and may crack.
Infiltration is dependent on the molten binder metal flowing around
the grains of the hard matrix particles and attaching to the matrix
grains. For a complete infiltration, the binder metal thoroughly
melts to allow for good flow and attachment. However, in the case
of diamond-impregnated bit bodies, in which diamond is also mixed
in or embedded with the matrix particles, the high infiltration
temperature (e.g., 1875.degree. to 2100.degree. F.) for long
periods of time compromises the diamond as well as increases the
thermal crack tendency of the bit body.
SUMMARY
[0004] This summary is provided to introduce a selection of
concepts that are further described below in the detailed
description. This summary is not intended to identify key or
essential features of the claimed subject matter, nor is it
intended to be used as an aid in limiting the scope of the claimed
subject matter.
[0005] In some embodiments, a binder metal composition has a
melting point of about 1500.degree. F. or less, and the binder
metal includes zinc (Zn) and tin (Sn) having a sum weight % of
about 26.5% to about 30.5% in which Zn is at least about 12% and Sn
is at least about 6.5%; nickel (Ni) is at about 4.5 to about 6.5
weight %; manganese (Mn) is at about 11 to about 26 weight %; and
copper (Cu) is at about 40 to about 55 weight %. In some
embodiments, the binder metal composition does not include
manganese (Mn). The binder metal as disclosed is used as an
infiltrant for infiltrating hard matrix particles at an
infiltration temperature of 1800.degree. F. or less and maintains a
strength and toughness that is comparable to matrices made with
presently available binder metals.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Embodiments of the binder metal are described with reference
to the following figures.
[0007] FIGS. 1-6 show temperature-dependent heat flow curves
calculated from differential scanning calorimetry (DSC) for each of
the respective binder metals represented by Formula-2, Formula-3,
Formula-4, Formula-5, Formula-6, and Comparative Formula-1, in
which the top line represents the heating curve (5) and the bottom
line represents the cooling curve (10), and the measured melting
point temperature is the indicated peak (15) of the heating curve
(5), according to one or more embodiments.
[0008] FIG. 7 is a scanning electron micrograph (SEM) image showing
the binder structure of an infiltrated metal-matrix composite made
from tungsten carbide particles and the Comparative Formula-1
Cu-rich binder metal etched with Spinodal etchant, with tungsten
carbide (20) and Cu-rich phase (25), as indicated.
[0009] FIG. 8 is an energy dispersive spectroscopy (EDS) spectrum
showing the single Cu-rich FCC (face-centered cubic) phase (25) of
the Comparative Formula-1 metal-matrix composite of FIG. 7.
[0010] FIG. 9 is a scanning electron micrograph (SEM) image showing
the binder structure of a metal-matrix composite made of tungsten
carbide particles and Formula-4 binder metal, according to one or
more embodiments, the metal-matrix composite etched with Spinodal
etchant.
[0011] FIG. 10 is an EDS spectrum of the Sn- and Ni-rich FCC phase
(35) for the Formula-4 metal-matrix composite of FIG. 9, according
to one or more embodiments.
[0012] FIG. 11 is an EDS spectrum of the Cu- and Zn-rich FCC phase
(30) for the Formula-4 metal-matrix composite of FIG. 9, according
to one or more embodiments.
[0013] FIG. 12 shows three optical microscopic (OM) images of solid
matrices of infiltrated tungsten carbide and Formula-4 binder
metal, according to one or more embodiments, at three infiltration
temperatures of 1950.degree. F., 1800.degree. F., and 1700.degree.
F., as shown, in which the eta-phase (40), monocrystal tungsten
carbide (20) and cast tungsten carbide (22) are indicated.
[0014] FIG. 13 is a transmission electron microscope (TEM) image of
Comparative Formula-1 binder metal, in which the measured FCC
lattice parameter is a=3.75 .ANG. (as a reference, a.sub.Cu=3.61
.ANG.), the single FCC phase Cu-rich binder (45) is indicated.
[0015] FIG. 14 shows a selected area diffraction (SAD) pattern for
the TEM image of FIG. 13.
[0016] FIG. 15 is a TEM image of the FCC-1 phase (50) of Formula-3,
according to one or more embodiments in which the measured FCC
lattice parameter is a=3.69 .ANG..
[0017] FIG. 16 shows a SAD pattern of the TEM image of FIG. 15.
[0018] FIG. 17 is a TEM image of the FCC-2 phase (55) of Formula-3,
according to one or more embodiments, in which the measured FCC
lattice parameter is a=6.15 .ANG..
[0019] FIG. 18 shows a SAD pattern of the TEM image of FIG. 17.
[0020] FIG. 19 shows a SAD pattern of the TEM image of FIG. 17
after tilting the sample to another angle from the TEM image of
FIG. 18.
[0021] FIG. 20 is a TEM image of the FCC-1 (50) and FCC-2 (55)
phases of a Formula-3 binder metal, according to one or more
embodiments, at a lower magnification than the TEM images of FIGS.
15 and 17.
DETAILED DESCRIPTION
[0022] An earth-boring drill bit body may be made from a
metal-matrix composite which includes a hard particulate phase and
a ductile metallic phase. The hard phase includes refractory or
ceramic compounds (e.g., nitrides and carbides, such as tungsten
carbide), and the metallic phase may be a binder metal, such as a
metal made of copper and other nonferrous alloys. The metal-matrix
composite may be formed using powder (i.e., particle) metallurgical
methods which include hot-pressing, sintering, and infiltration.
Drill bit bodies may have at least a portion of their outer surface
impregnated with an ultra-hard material. Such bit bodies are
referred to as ultra-hard material impregnated bit bodies. For
ultra-hard material impregnated drill bit bodies, the metal-matrix
composite also serves as a supporting material for supporting the
ultra-hard material. In such embodiments, the metal-matrix
composite has specifically controlled physical and mechanical
properties in order to expose the ultra-hard material. Methods of
forming drill bit bodies are described in U.S. Pat. No. 6,394,202
and U.S. Pat. No. 8,109,177, the entire contents of both of which
are herein incorporated by reference. Some examples of drill bit
bodies include impregnated drill bit bodies, impregnated drill bit
bodies having grit hot-pressed inserts (GHIs), and polycrystalline
diamond compact (PDC) drill bit bodies.
[0023] As described, infiltration of the metal-matrix composite
includes heating the metal-matrix to a temperature that is high
enough to allow for the binder metal (also referred to as the
infiltrant) to melt and bind to the hard particulate phase. As
such, during infiltration of the metal-matrix composite, the binder
metal becomes molten and flows and attaches to the grains of the
hard particulate. Accordingly, the melting point temperature of the
binder metal directly determines the infiltration temperature for
forming the metal-matrix composite. As used herein, the melting
point or the melting temperature is the liquidus temperature of the
particular composition, as described in Hsin Wang and Wallace
Porter, Thermal Conductivity 27/Thermal Expansion 15, October 2004
(ISBN-10: 1932078347|ISBN-13: 978-1932078343), the entire contents
of which are herein incorporated by reference.
[0024] According to one or more embodiments, a binder having a
melting point of 1500.degree. F. or less, allows for an
infiltration temperature that is about 1800.degree. F. or lower,
and results in improved phases of the metal-matrix composite. In
some embodiments, the face centered cubic-1 (FCC-1) phase and FCC-2
phase of the composite formed with such binder metal are in an
approximate balance. That is, the FCC-1 to FCC-2 ratio is 1-1.5
(FCC-1) to 1.0 (FCC-2). In addition, at a lower infiltration
temperature of about 1800.degree. F. or less, there is a decrease
in the eta-phase of the composite. A drill bit body formed with a
composite having a decrease in eta-phase and an approximate
(1.0-1.5:1.0) balance of FCC-1 to FCC-2 phases has a decreased
thermal cracking tendency.
[0025] Examples of ultra-hard materials used in impregnated drill
bit bodies, include polycrystalline diamond (PCD), and thermally
stable polycrystalline diamond (TSP) all of which are well known in
the art. Examples of PCD and TSP materials are described in U.S.
Pat. No. 8,020,644, the entire contents of which are fully
incorporated herein by reference. TSP materials may be formed using
any suitable binder, for example, cobalt or silicon carbide binder.
Furthermore, a higher density TSP material is formed from a higher
density PCD material which utilizes less cobalt binder. In some
embodiments, when forming an ultra-hard material impregnated bit
body, the metal-matrix composite is formed by infiltrating with the
presently disclosed lower melting point temperature binder metal at
an infiltration temperature of about 1800.degree. F. In some
embodiments, the metal matrix composite is formed by infiltrating
with the presently disclosed lower melting point temperature binder
metal at an infiltration temperature of about 1800.degree. F. in
forming an impregnated drill bit body which is impregnated with PCD
or TSP (sometimes referred to as a diamond impregnated drill bit
body), resulting in the diamond being less likely to be compromised
in the manufacturing of the diamond-impregnated drilling bit
bodies.
[0026] One or more embodiments include a binder metal composition
having a melting point temperature of 1500.degree. F. or less, in
which the binder metal includes an increased amount of tin (Sn) and
zinc (Zn) and a specific sum of these two metals, in addition to
copper (Cu), manganese (Mn), and nickel (Ni). As disclosed herein,
a binder metal composition for use in making drill bit body
components has a melting point temperature of 1500.degree. F. or
less and thoroughly melts to allow for good flow and attachment to
the hard particulate matrix grains at a lower infiltration
temperature (e.g., 1800.degree. F. or lower), thereby effectively
lowering the thermal crack tendency of the drill bit body.
[0027] In some embodiments, a binder metal composition having a
lower melting point temperature has comparable strength to binder
metal compositions having higher melting point temperatures. That
is, specific increases in Sn or Zn in the binder metal composition
effectively lower the melting point temperature of the binder metal
and do not compromise the bonding capability, strength, or
toughness of the binder metal.
[0028] Using thermodynamic modeling to perform equilibrium phase
diagram of multi-component alloy system and to simulate the
solidification process (under Gulliver-Scheil non-equilibrium
condition), Cu--Mn--Ni--Zn--Sn binder metal alloy compositions
having a melting point temperature of 1500.degree. F. or less were
determined in which the total weight amount of Sn and Zn together
was increased compared to presently used binder metals, without
compromising the bonding capability, strength, or toughness.
Indeed, the solid metallic matrices made using a binder metal as
disclosed herein have two phases compared to the single phased
matrices using other binder metals (e.g., a binder metal of
Comparative Formula-1 as described in Table 1, having a measured
melting point of 1655.degree. F.).
[0029] As used herein, the term "about" preceding a value refers to
the value including 0.5 less than the value and 0.5 more than the
value.
[0030] In some embodiments, a binder metal composition has a
melting point of 1500.degree. F. or less and includes Cu, Mn, Ni,
Zn, and Sn in which Sn is at least at about 6.5 weight %, and Sn
and Zn together equal a total weight amount of about 26.5% to about
30.5%; Ni is present at about 4.5 to about 6.5 weight %; Mn is
present at about 11 to about 26 weight %; and Cu is present at
about 40 to about 55 weight %.
[0031] In other embodiments, the composition does not include
manganese and is weight balanced with copper. For example, Sn is at
least at about 6.5 weight %, and Sn and Zn together equal a total
weight amount of about 26.5% to about 30.5%; Ni is present at about
4.5 to about 6.5 weight %; and Cu is present at about 51 to about
81 weight %.
[0032] In some embodiments, a binder metal composition has a
melting point of 1500.degree. F. or less and includes Cu, Mn, Ni,
Zn, and Sn in which Sn is at least at about 6.75 weight %, and Sn
and Zn together equal a total weight amount of about 26.5% to about
30.5%, Ni is present at about 4.5 to about 6.5 weight %; Mn is
present at about 14 to about 21 weight %; and Cu is present at
about 45 to about 52 weight %.
[0033] In some embodiments, a binder metal composition has a
melting point of 1500.degree. F. or less and includes Cu, Mn, Ni,
Zn, and Sn in which Sn is at least at about 6.75 weight %, and Sn
and Zn together equal a total weight amount of about 26.5% to about
30.5%, Ni is present at about 4.5 to about 6.5 weight %; Mn is
present at about 17 weight %; and Cu is present at about 49%.
[0034] In some embodiments, a binder metal composition has a
melting point of 1500.degree. F. or less and includes Cu, Mn, Ni,
Zn, and Sn in which Sn is present in a weight amount of about 6.75%
to about 16%; Zn is present in a weight amount of about 12% to
about 22.75%; Ni is present in a weight amount of about 4.5% to
about 6.5%; Mn is present in a weight amount of about 11 to about
26%; and Cu is present in a weight amount of about 40 to about
55%.
[0035] In other embodiments, a binder metal composition has a
melting point of 1500.degree. F. or less and includes Cu, Mn, Ni,
Zn, and Sn represented herein by Formula 2 (For-2), in which Sn is
present in a weight amount of about 16%; Zn is present in a weight
amount of about 12%; Ni is present in a weight amount of about 6%;
Mn is present in a weight amount of about 17%; and Cu is present in
a weight amount of about 49%. FIG. 1 shows the DSC temperature
curves for a Formula-2 binder metal, with the measured melting
point at peak (15) of the heating curve (5). As shown in FIG. 1,
the measured melting point for a binder metal of Formula 2 is
771.degree. C. (1420.degree. F.).
[0036] In other embodiments, a binder metal composition has a
melting point of 1500.degree. F. or less and includes Cu, Mn, Ni,
Zn, and Sn represented herein by Formula 3 (For-3), in which Sn is
present in a weight amount of about 10%; Zn is present in a weight
amount of about 19%; Ni is present in a weight amount of about 5%;
Mn is present in a weight amount of about 17%; and Cu is present in
a weight amount of about 49%. FIG. 2 shows the DSC temperature
curves for a Formula-3 binder metal with the measured melting point
at peak (15) of the heating curve (5). As shown in FIG. 2, the
measured melting point for a binder metal of Formula 3 is
798.degree. C. (1468.degree. F.).
[0037] In other embodiments, a binder metal composition has a
melting point of 1500.degree. F. or less and includes Cu, Mn, Ni,
Zn, and Sn represented herein by Formula 4 (For-4), in which Sn is
present in a weight amount of about 13%; Zn is present in a weight
amount of about 15.5%; Ni is present in a weight amount of about
5.5%; Mn is present in a weight amount of about 17%; and Cu is
present in a weight amount of about 49%. FIG. 3 shows the DSC
temperature curves for a Formula-4 binder metal, with the measured
melting point at peak (15) of the heating curve (5). As shown in
FIG. 3, the measured melting point for a binder metal of Formula 4
is 779 C (1434.degree. F.).
[0038] In other embodiments, a binder metal composition has a
melting point of 1500.degree. F. or less and includes Cu, Mn, Ni,
Zn, and Sn represented herein by Formula 5 (For-5), in which Sn is
present in a weight amount of about 15%; Zn is present in a weight
amount of about 12.5%; Ni is present in a weight amount of about
6.5%; Mn is present in a weight amount of about 17%; and Cu is
present in a weight amount of about 49%. FIG. 4 shows the DSC
temperature curves for a Formula-5 binder metal, with the measured
melting point at peak (15) of the heating curve (5). As shown in
FIG. 4, the measured melting point for a binder metal of Formula 5
is 779.degree. C. (1434.degree. F.).
[0039] In other embodiments, a binder metal composition has a
melting point of 1500.degree. F. or less and includes Cu, Mn, Ni,
Zn, and Sn represented herein by Formula 6 (For-6), in which Sn is
present in a weight amount of about 6.75%; Zn is present in a
weight amount of about 22.75%; Ni is present in a weight amount of
about 4.5%; Mn is present in a weight amount of about 17%; and Cu
is present in a weight amount of about 49%. FIG. 5 shows the DSC
temperature curves for a Formula-6 binder metal, with the measured
melting point at peak (15) of the heating curve (5). As shown in
FIG. 5, the measured melting point for a binder metal of Formula 6
is 811.degree. C. (1492.degree. F.).
[0040] FIG. 6 shows the DSC temperature curve for Comparative
Formula-1, with the measured melting point at peak (15) of the
heating curve (5). As shown in FIG. 6, the measured melting point
for a binder metal of Comparative Formula-1 is 902.degree. C.
(1655.degree. F.).
[0041] Table 1 below shows the formulae and the measured melting
point temperatures (from DSC curves of FIGS. 1-6) for Formulae 2,
3, 4, 5, and 6, and Comparative Formula-1, as well as the
crystallographic properties (based on the thermodynamic
calculation). The crystallographic properties as indicated include
the face-centered cubic (FCC) data for each alloy.
TABLE-US-00001 TABLE 1 Calculated mole Measured Sample Chemistry
fraction of Calculated MP(.degree. F.) BinderMetalAlloy (weight
percentage) solid solution MP (.degree. F.) by DSC Comparative
55Cu12Ni23Mn4Zn6Sn 0.980FCC-1- 1702 1655 Formula-1 0.013FCC-2
Formula-2 49Cu6Ni17Mn12Zn16Sn 0.503FCC-1- 1482 1420 0.458FCC-2
Formula-3 49Cu5Ni17Mn19Zn10Sn 0.592FCC-1- 1518 1468 0.395FCC-2
Formula-4 49Cu5.5Ni17Mn15.5Zn13Sn 0.559FCC-1- 1502 1434 0.419FCC-2
Formula-5 49Cu6.5Ni17Mn12.5Zn15Sn 0.594FCC-1- 1500 1434 0.375FCC-2
Formula-6 49Cu4.5Ni17Mn22.75Zn6.75Sn 0.594FCC-1- 1530 1492
0.398FCC-2
[0042] According to some embodiments, binder metals having a
melting point temperature of 1500.degree. F. or less have balanced
solid solution FCC-1/FCC-2 microstructure properties which are not
found in other binder metals, e.g., a binder metal of Comparative
Formula-1. The balance of FCC-1 (30) and FCC-2 (35) phases in a
metal-matrix composite made from a binder metal of Formula-4 is
shown in the SEM images (FIG. 9), and the corresponding
semi-quantitative chemistry is provided in the energy dispersion
spectroscopy (EDS) (FIGS. 10 and 11). This dual phase metal matrix
(FCC-1 (50) and FCC-2 (55)) for the Formula-3 binder is also
resolved in the TEM images of FIGS. 15, 17 and 20. In contrast, the
binder metal of Comparative Formula-1 is resolved in the SEM and
EDS images of FIGS. 7 and 8, in which the single FCC-1 (25) binder
metal phase dominates the metal-matrix composite. The single FCC-1
phase (45) of the binder metal of Comparative Example 1 is also
resolved in a TEM image as shown in FIG. 13. These observations are
in agreement with the multi-component thermodynamic modeling, as
shown in Table 1. (The difference in the calculated melting point
and the measured values is due to the extrapolated thermodynamic
database employed in this research and the variation in
chemistry.)
[0043] According to some embodiments, binder metals having a
melting point temperature of 1500.degree. F. or less are
infiltrated into the matrix particles (e.g. tungsten carbide) at
lower infiltration temperatures to form the metal-matrix composite
used in drill bit bodies. The optical microscopy (OM) images of
FIG. 12 show the formation of a reaction layer around the cast
tungsten carbide (20) at an infiltration temperature of
1950.degree. F., 1800.degree. F. and 1700.degree. F., as indicated.
The lower infiltration temperature reduces the dissolution of cast
tungsten carbide (22) and suppresses the formation of brittle
phases, such as the carbon-deficient eta-phases (40). Furthermore,
lower infiltration temperature preserves the integrity of
diamond.
[0044] In some embodiments, the binder metal composition includes
an additive element in which the additive element is up to about 5%
of the binder metal composition by weight. For example, an additive
element includes boron, silicon, iron, cobalt, aluminum, titanium,
niobium, molybdenum, tungsten and or combinations thereof. For
example, the binder metal composition may include both boron and
silicon. In some embodiments, boron and silicon are added together
up to about 5% of the binder metal composition by weight. In some
embodiments boron and silicon are added together up to about 0.5%
by weight. In some embodiments, boron is included from 0.05 to
0.07% weight and silicon is added from 0.15 to 0.18% by weight.
[0045] In some embodiments, the metal-matrix composite having the
lower melting point binder metal as disclosed herein is used in the
fabrication of drill bit bodies having a plurality of blades (e.g.,
ribs) disposed on the drill bit body and cutting elements, for
example, as described in detail in U.S. Pat. No. 8,020,644, the
entire contents of which are incorporated herein by reference. As
described in this incorporated reference, the metal-matrix
materials may be combined with varying hard particles to make
various aspects of the drill bit body having blades and cutting
elements. The metal-matrix composite for the disclosed components
in U.S. Pat. No. 8,100,203 may include the disclosed lower melting
point binder metal, having a melting point of 1500.degree. F. or
less. (The entire contents of U.S. Pat. No. 8,100,203 are herein
incorporated by reference.) For example, in some embodiments, a bit
body made using a metal-matrix composite made with the presently
disclosed lower melting point binder metal, includes a blade or
blades having diamond grit. In other embodiments, polycrystalline
diamond compact (PDC) inserts having a substrate made from a
metal-matrix composite made with the presently disclosed lower
melting point binder metal are attached to a drill bit body. In
other embodiments, thermally stable polycrystalline diamond (TSP)
cutting elements include a substrate made from a metal-matrix
composite made with the presently disclosed lower melting point
binder metal. Methods using PCD or TSP cutting elements are known
in the art, and for example, are described in U.S. Pat. No.
6,892,836 and U.S. Patent Publication No. 2010/0126779, the entire
contents of both of which are herein incorporated by reference. In
another example, the presently disclosed lower melting point binder
metal is used as the infiltrant in forming grit hot pressed inserts
(GHIs), as described, for example, in U.S. Pat. No. 6,394,202 and
U.S. Pat. No. 8,109,77, the entire contents of both of which are
herein incorporated by reference. In all of the aforementioned
embodiments, the lower melting point metal binders disclosed herein
may be used in lieu of the binder metals disclosed in the cited
references.
[0046] The following Examples are presented for illustrative
purposes only, and do not limit the scope or content of the present
application.
EXAMPLES
Example 1
Properties of Binder Metal of Formulae 2-6
[0047] As shown below in Table 2, the mechanical and energetic
properties of binder metals of Formulae 2-6 were analyzed and the
data is shown in comparison to the binder metal of Comparative
Formula-1.
TABLE-US-00002 TABLE 2 Comparative Formulae-2, 3, Formula-1 4, 5, 6
Melting point (.degree. F.) 1655 1420-1492 Infiltration Temp
(.degree. F.) 1950 .ltoreq.1800 TRS (GM15 infiltrated @ 137 .+-. 6
121 .+-. 5 1800.degree. F.) (ksi) K.sub.IC (GM15 infiltrated @ 18.6
.+-. 1.8 16.1 .+-. 1.1 1800.degree. F.) (ksi in.sup.1/2)
[0048] The infiltration temperature is the temperature required to
melt the binder metal and allow for good flow of the binder metal
and attachment to the hard particulate grains (e.g. the tungsten
carbide grains). As shown in Table 2, the binder metals of Formulae
2, 3, 4, 5 and 6, have an infiltration temperature of 1800.degree.
F., which is approximately 300 degrees higher than the melting
point temperature of each of the binder metals of Formulae 2, 3, 4,
5 and 6. Comparatively, a binder metal of Comparative Formula-1,
having a melting point of 1655.degree. F., has an infiltration
temperature of 1950.degree. F., whereas the infiltration
temperature for a binder metal of Formulae 2-6 having a melting
point of 1500.degree. F. or less, can be infiltrated with the hard
phase matrix particles (e.g., tungsten carbide) at 1800.degree. F.
or less. In some embodiments, a binder metal as disclosed herein is
used for infiltrating at an infiltration temperature of about
1790.degree. F. In some embodiments, a binder metal as disclosed
herein is used for infiltrating at an infiltration temperature of
about 1780.degree. F. In other embodiments, a binder metal as
disclosed herein is used for infiltrating at an infiltration
temperature of about 1770.degree. F.
[0049] The transverse rupture strength (TRS) was measured on solid
matrices of tungsten carbide and binder metal for each of the
binder metals of Formula 2-6 and Comparative Formula-1. In Table 2,
the solid matrices using a binder metal of Formulae 2, 3, 4, 5 or 6
had a TRS of 121.+-.5 ksi (one thousand pounds per square inch),
which is comparable to the TRS of a solid metal-matrix composite
made from a binder metal of Comparative Formula-1.
[0050] Linear-Elastic Plane-Strain Fracture Toughness K.sub.IC of
the solid metal-matrix composite is measured using uniaxial bending
method and reported in inch pounds or ksiin.sup.1/2. The solid
matrices using a binder metal of Formulae 2, 3, 4, 5 or 6 have
comparable toughness to the toughness of a solid metal-matrix
composite made from a binder metal of Comparative Formula-1.
Example 2
Differential Scanning Calorimetry (DSC)
[0051] DSC analysis was performed following standard methods known
in the art. In brief, the melting of each binder metal was analyzed
using the NETZSCH model DSC 404 F1 Pegasus.RTM. differential
scanning calorimeter to measure the transformation energies of the
binder metals.
Example 3
Preparation of Solid Metal-Matrix Composite for OM and SEM
[0052] The solid metal matrix composite made of tungsten carbide
particles and the binder metal was formed by infiltrating the
tungsten carbide particles and the binder metal to form the solid
metal-matrix composite. Binder TEM sample was prepared by standard
procedure and final thinning process was completed by a Gatan
Precision Ion Polishing System (PIPS.TM.). TEM observation and
analysis was performed on a JEOL 2010 Transmission Electron
Microscope at an accelerating voltage of 200 kV. Selected area
diffraction (SAD) patterns were obtained for each TEM image. The
SAD pattern corresponding to the TEM image of FIG. 13 is shown in
FIG. 14. The SAD pattern corresponding to the TEM image of FIG. 15
is shown in FIG. 16, and the two SAD patterns at two different
angles corresponding to the TEM image of FIG. 17 are shown in FIGS.
18 and 19.
[0053] As disclosed throughout, a binder metal including Cu, Mn,
Ni, Zn and Sn, in which Zn and Sn have a sum weight % of 26.5% to
30.5% in which Zn is at least 12% and Sn is at least 6.75%, Ni is
at 4.5 to 6.5 weight %, Mn at 11 to 26 weight %; and Cu at 40 to 55
weight %, has a melting point of about 1500.degree. F. or less and
has a transverse rupture strength of 90-140 ksi varying with the
hard phase matrix particles. As discussed and shown in the figures
herein, the binder metal according to the disclosed embodiments is
infiltrated into the hard matrix particles at an infiltration
temperature of about 1800.degree. F. or less.
[0054] Although only a few example embodiments have been described
in detail above, those skilled in the art will readily appreciate
that many modifications are possible in the example embodiments
without materially departing from this invention. Accordingly, all
such modifications are without materially departing from this
invention. Accordingly, all such modifications are intended to be
included within the scope of this disclosure as defined in the
following claims. It is the express intention of the applicant not
to invoke 35 U.S.C. 112, paragraph 6 for any limitations of any of
the claims herein, except for those in which the claim expressly
uses the words `mean for` together with an associated function.
* * * * *