U.S. patent application number 14/679307 was filed with the patent office on 2015-10-08 for fine-grained high carbide cast iron alloys.
The applicant listed for this patent is Scoperta, Inc.. Invention is credited to Justin Lee Cheney.
Application Number | 20150284829 14/679307 |
Document ID | / |
Family ID | 54209241 |
Filed Date | 2015-10-08 |
United States Patent
Application |
20150284829 |
Kind Code |
A1 |
Cheney; Justin Lee |
October 8, 2015 |
FINE-GRAINED HIGH CARBIDE CAST IRON ALLOYS
Abstract
Embodiments of alloys having high, fine-grained carbide content,
and methods of manufacturing such alloys. The alloys can be
determined through the use of thermodynamic, microstructural, and
compositional criterial in order to create a high strength and high
toughness alloy. In some embodiments, the alloys can be used as a
wear resistant component.
Inventors: |
Cheney; Justin Lee;
(Encinitas, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Scoperta, Inc. |
San Diego |
CA |
US |
|
|
Family ID: |
54209241 |
Appl. No.: |
14/679307 |
Filed: |
April 6, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61976438 |
Apr 7, 2014 |
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Current U.S.
Class: |
420/12 ;
164/47 |
Current CPC
Class: |
C22C 37/10 20130101;
C22C 33/0292 20130101; C22C 37/08 20130101; C22C 37/06 20130101;
C22C 33/0285 20130101; C22C 30/00 20130101; B23K 35/308 20130101;
C22C 33/08 20130101; B23K 35/3086 20130101; C21D 2211/004
20130101 |
International
Class: |
C22C 37/06 20060101
C22C037/06; B22D 25/06 20060101 B22D025/06; C22C 33/08 20060101
C22C033/08; C22C 37/08 20060101 C22C037/08; C22C 37/10 20060101
C22C037/10 |
Claims
1. An article of manufacture comprising: an alloy comprising Fe,
Cr, and C; wherein a total carbide and boride content in a
microstructure of the alloy exceeds 40 volume %; and wherein a
grain size of all carbides and borides is less than or equal to 50
micrometers in their longest dimension.
2. The article of manufacture of claim 1, wherein the alloy is an
iron based alloy and comprises: C: 2.2-4.02 wt. %; and Cr: 10-34
wt. %.
3. The article of manufacture of claim 1, wherein the alloy
comprises: C: 2.5-3.8 wt. %; Cr: 10-28 wt. %; Nb: 0-5 wt. %; and W:
0-9 wt. %.
4. The article of manufacture of claim 3, wherein the alloy further
comprises: Mn: 0-1 wt. %; Mo: 0-1 wt. %; Si: 0-1 wt. %; Ti: 0-0.5
wt. %; and V: 0-3 wt. %.
5. The article of manufacture of claim 1, wherein the alloy
comprises: C: 2.2-4.02 wt. %; Cr: 12.7-34 wt. %; Nb: 3.8-5 wt. %;
and W: 4.37-9 wt. %.
6. The article of manufacture of claim 1, wherein the total carbide
and boride content exceeds 45 volume %.
7. The article of manufacture of claim 6, wherein the total carbide
and boride content exceeds 50 volume %.
8. The article of manufacture of claim 1, wherein the grain size of
all carbides and borides does not exceed 25 micrometers in their
longest dimension.
9. The article of manufacture of claim 8, wherein the grain size of
all carbides and borides does not exceed 5 micrometers in their
longest dimension.
10. The article of manufacture of claim 1, wherein the article of
manufacture comprises a sleeve or layer for use in pipelines
designed to carry abrasive slurries.
11. A wear resistant component comprising the article of
manufacture of claim 1.
12. An article of manufacture comprising: an alloy comprising Fe,
Cr, and C; wherein a total carbide and boride content in a
microstructure of the alloy exceeds 0.4 mole fraction; and wherein
a total volume of segregated carbides is less than 0.05 mole
fraction, segregated carbides being defined as Fe or Cr-rich boride
or carbide meeting the equation: Fe+Cr>50 wt. %, wherein the
segregated carbides are thermodynamically stable at a temperature
above a temperature at which austenite of the alloy is
thermodynamically stable.
13. The article of manufacture of claim 12, wherein the alloy is an
iron based alloy and comprises: C: 2.2-4.02 wt. %; and Cr: 10-34
wt. %.
14. The article of manufacture of claim 12, wherein the alloy
comprises: C: 2.5-3.8 wt. %; Cr: 10-28 wt. %; Nb: 0-5 wt. %; and W:
0-9 wt. %.
15. The article of manufacture of claim 13, wherein the alloy
further comprises: Mn: 0-1 wt. %; Mo: 0-1 wt. %; Si: 0-1 wt. %; Ti:
0-0.5 wt. %; and V: 0-3 wt. %.
16. The article of manufacture of claim 12, wherein the alloy
comprises: C: 2.2-4.02 wt. %; Cr: 12.7-34 wt. %; Nb: 3.8-5 wt. %;
and W: 4.37-9 wt. %.
17. The article of manufacture of claim 12, wherein the total
carbide and/or boride content exceeds 0.45 mole fraction.
18. The article of manufacture of claim 17, wherein the total
carbide and/or boride content exceeds 0.50 mole fraction.
19. The article of manufacture of claim 12, wherein the article of
manufacture comprises a sleeve or layer used in pipelines designed
to carry abrasive slurries.
20. A wear resistant component comprising the article of
manufacture of claim 12.
21. A method of forming a component comprising: providing an alloy
comprising Fe, Cr, and C; wherein a total carbide and boride
content in a microstructure of the alloy exceeds 40 volume %; and
wherein a grain size of all carbides and borides is less than or
equal to 50 micrometers in their longest dimension; and forming a
component from the alloy.
22. The method of claim 21, wherein the alloy is an iron-based
alloy and comprises: C: 2.2-4.02 wt. %; and Cr: 10-34 wt. %.
23. The method of claim 21, wherein the alloy comprises: C: 2.5-3.8
wt. %; Cr: 10-28 wt. %; Nb: 0-5 wt. %; W: 0-9 wt. %; Mn: 0-1 wt. %;
Mo: 0-1 wt. %; Si: 0-1 wt. %; Ti: 0-0.5 wt. %; and V: 0-3 wt.
%.
24. The method of claim 21, wherein the alloy comprises: C:
2.2-4.02 wt. %; Cr: 12.7-34 wt. %; Nb: 3.8-5 wt. %; and W: 4.37-9
wt. %.
25. The method of claim 21, wherein the total carbide and/or boride
content exceeds 0.45 mole fraction.
26. The method of claim 25, wherein the total carbide and/or boride
content exceeds 0.50 mole fraction.
27. The method of claim 21, wherein forming the component comprises
forming the component via a casting process.
28. The method of claim 21, wherein forming the component comprises
forming the component into a sleeve or layer.
Description
INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS
[0001] Any and all applications for which a foreign or domestic
priority claim is identified in the Application Data Sheet as filed
with the present application are hereby incorporated by reference
under 37 CFR 1.57.
BACKGROUND
[0002] 1. Field
[0003] The disclosure relates generally to cast iron alloys used in
wear-prone environments and which are resistant to wear.
[0004] 2. Description of the Related Art
[0005] The alloy family known as chromium white irons or chromium
white cast irons can refer to alloys containing Fe, C, and Cr which
can form eutectic chromium carbides. For example, alloys having
chromium levels in the range from 15-30 wt. % (or about 15 to about
30 wt. %) and having carbon levels in the range of 1-3 wt. % (or
about 1 to about 3 wt. %) can form such chromium white irons. For
chromium white irons, formation of primary chromium carbides is
typically avoided which can occur as either Cr or C content is
increased. For many applications, particularly those which require
a minimum level of toughness, it can be advantageous for the alloy
system to be in the hypoeutectic region of the Fe--C phase field
(i.e., the C level is below the eutectic point in the alloy
system). Exceeding the C eutectic level in these systems can create
Cr.sub.7C.sub.3 carbide precipitates which are long, rod-like, and
can be very embrittling to the material. Further, the addition of
chromium can shift the eutectic point to more iron-rich
compositions. Therefore, as Cr is added for various benefits (such
as corrosion resistance), the amount of carbon which can be added
before the alloy enters the hypereutectic regime drops. For
example, an Fe-5Cr type alloy has a eutectic point over .about.4% C
while an Fe-25Cr alloy has a eutectic point at around 3.3% C.
[0006] Chromium white irons are generally very useful for
applications where resistance to abrasion is advantageous. The
relatively high content of chromium carbides in the microstructure
are very hard and thus contribute to the abrasion resistance of the
material. In part, the volume fraction of carbides in the alloy can
dictate the wear resistance of the material, e.g., increased
carbide contents can create increased wear resistance. In some
applications, the carbon beyond the eutectic point can be increased
to increase the total carbide fraction. However, this is done at
the expense of toughness.
[0007] International Patent No. WO 84/04760, hereby incorporated by
reference in its entirety, describes a mechanism for producing both
tough and wear resistant high chromium hypereutectic white irons.
WO 84/04760 teaches that a minimum amount of primary M.sub.7C.sub.3
carbides are required to achieve the tough and wear resistant high
chromium hypereutectic white irons, and it is discussed that
refinement of the microstructure and increased toughness can be
achieved through process control. International filing WO 85/01962,
hereby incorporated by reference in its entirety, also teaches
improved toughness through microstructural control, utilizing
super-cooling (or process control) and boron to produce globular
shaped carbides. U.S. Pat. No. 6,669,790, hereby incorporated by
reference in its entirety, teaches that primary chromium carbides
must be completely eliminated. To achieve this, vanadium, titanium,
and niobium primary carbides are used to increase the total carbide
content while maintaining toughness.
SUMMARY
[0008] In some embodiments, computational metallurgy can be used to
explore alloy compositional ranges where the total carbide content
can be increased without introducing coarse carbide structures
known to embrittle the material. When considering the Fe--Cr--C
system, the thermodynamic limit for hypoeutectic carbide volume
fraction can be 35-40% (or about 35-about 40%). This disclosure
describes embodiments of alloys which can meet a set of
thermodynamic criteria which can exceed the 40% (or about 40%)
carbide content limit, but may not introduce the formation of
hypereutectic M.sub.7C.sub.3, M.sub.23C.sub.6 or generally any
Fe,Cr-rich type carbides. The result is a microstructure which can
have a very high level, >40% mole fraction (or >about 40%
mole fraction) as defined by thermodynamic models, of fine-grained
carbides. As such, this new class of materials can be defined as
fine-grained high carbide content cast irons. The utility of such a
material can be an increased wear resistance, while maintaining
similar levels of toughness to hypoeutectic cast irons.
[0009] Disclosed herein are embodiments of an article of
manufacture which can contain in at least a portion of its
structure a component comprising Fe, Cr, and C in which the total
carbide and/or boride content in the microstructure exceeds 40
volume %, and the grain size of all carbides and borides does not
exceed 50 micrometers in their longest dimension.
[0010] In some embodiments, the alloy further can further comprise
C: 2.5-3.8 wt. %, Cr: 10-28 wt. %, Nb: 0-5 wt. %, W: 0-9 wt %. In
some embodiments, the alloy can further comprise Mn: 0-1 wt %, Mo:
0-1 wt %, Si: 0-1%, Ti: 0-0.5%, V: 0-3 wt. %. In some embodiments,
the alloy further can further comprise C: 2.2-4.02 wt. %, Cr:
12.7-34 wt. %, Nb: 3.8-5 wt. %, W: 4.37-9 wt %.
[0011] In some embodiments, the total carbide and/or boride content
can exceed 45 volume %. In some embodiments, the total carbide
and/or boride content can exceed 50 volume %.
[0012] In some embodiments, the grain size of all carbides and
borides does not exceed 25 micrometers in their longest dimension.
In some embodiments, the grain size of all carbides and borides
does not exceed 5 micrometers in their longest dimension.
[0013] In some embodiments, the article can be produced via the
casting process. In some embodiments, the article can be utilized
as a wear resistant component. In some embodiments, the article can
be used as a sleeve or layer in pipelines designed to carry
abrasive slurries
[0014] Further disclosed herein is an article of manufacture which
can comprise Fe, Cr, and C in which the total carbide and/or boride
content in the microstructure exceeds 40 volume %, and the grain
size of all carbides and borides does not exceed 50 micrometers in
their longest dimension.
[0015] Further disclosed herein is an article of manufacture which
can contain at least a portion of a component comprising Fe, Cr,
and C in which the total carbide and/or boride content in the
microstructure exceeds 0.4 mole fraction, and the total volume of
segregated carbides is less than 0.05 mole fraction, whereas a
segregated carbide is defined as Fe or Cr-rich boride or carbide,
Fe+Cr>50 wt. %, which is thermodynamically stable at a
temperature above the temperature at which austenite is
thermodynamically stable.
[0016] In some embodiments, the alloy can further comprise C:
2.5-3.8 wt. %, Cr: 10-28 wt. %, Nb: 0-5 wt. %, W: 0-9 wt %. In some
embodiments, the alloy can further comprise Mn: 0-1 wt %, Mo: 0-1
wt %, Si: 0-1%, Ti: 0-0.5%, V: 0-3 wt. %. In some embodiments, the
alloy can further comprise C: 2.2-4.02 wt. %, Cr: 12.7-34 wt. %,
Nb: 3.8-5 wt. %, W: 4.37-9 wt %.
[0017] In some embodiments, the total carbide and/or boride content
can exceed 0.45 mole fraction. In some embodiments, the total
carbide and/or boride content can exceed 0.50 mole fraction.
[0018] In some embodiments, the article can be produced via the
casting process. In some embodiments, the article can be utilized
as a wear resistant component. In some embodiments, the article can
be used as a sleeve or layer in pipelines designed to carry
abrasive slurries
[0019] Also disclosed herein is a method of forming a component
which can contain in at least a portion of its structure a
component comprising Fe, Cr, and C in which the total carbide
and/or boride content in the microstructure exceeds 40 volume %,
and the grain size of all carbides and borides does not exceed 50
micrometers in their longest dimension.
[0020] In some embodiments, the alloy can further comprise C:
2.5-3.8 wt. %, Cr: 10-28 wt. %, Nb: 0-5 wt. %, W: 0-9 wt %. In some
embodiments, the alloy can further comprise Mn: 0-1 wt %, Mo: 0-1
wt %, Si: 0-1%, Ti: 0-0.5%, V: 0-3 wt. %. In some embodiments, the
alloy can further comprise C: 2.2-4.02 wt. %, Cr: 12.7-34 wt. %,
Nb: 3.8-5 wt. %, W: 4.37-9 wt %.
[0021] In some embodiments, the total carbide and/or boride content
can exceed 0.45 mole fraction. In some embodiments, the total
carbide and/or boride content can exceed 0.50 mole fraction.
[0022] In some embodiments, the article can be produced via the
casting process. In some embodiments, the article can be utilized
as a wear resistant component. In some embodiments, the article can
be used as a sleeve or layer in pipelines designed to carry
abrasive slurries.
[0023] Disclosed herein are embodiments of an article of
manufacture comprising an alloy comprising Fe, Cr, and C, wherein a
total carbide and boride content in a microstructure of the alloy
exceeds 40 volume %, and wherein a grain size of all carbides and
borides is less than or equal to 50 micrometers in their longest
dimension.
[0024] In some embodiments, the alloy can be an iron based alloy
and can comprise C: 2.2-4.02 wt. % and Cr: 10-34 wt. %. In some
embodiments, the alloy can comprise C: 2.5-3.8 wt. %, Cr: 10-28 wt.
%, Nb: 0-5 wt. %, and W: 0-9 wt. %. In some embodiments, the alloy
can further comprise Mn: 0-1 wt. %, Mo: 0-1 wt. %, Si: 0-1 wt. %,
Ti: 0-0.5 wt. %, and V: 0-3 wt. %. In some embodiments, the alloy
can comprise C: 2.2-4.02 wt. %. Cr: 12.7-34 wt. %, Nb: 3.8-5 wt. %,
and W: 4.37-9 wt. %.
[0025] In some embodiments, the total carbide and boride content
can exceed 45 volume %. In some embodiments, the total carbide and
boride content can exceed 50 volume %.
[0026] In some embodiments, the grain size of all carbides and
borides may not exceed 25 micrometers in their longest dimension.
In some embodiments, the grain size of all carbides and borides may
not exceed 5 micrometers in their longest dimension.
[0027] In some embodiments, the article of manufacture can comprise
a sleeve or layer for use in pipelines designed to carry abrasive
slurries. Also disclosed herein are embodiments of a wear resistant
component comprising embodiments of the disclosed article of
manufacture.
[0028] Also disclosed are embodiments of an article of manufacture
comprising an alloy comprising Fe, Cr, and C, wherein a total
carbide and boride content in a microstructure of the alloy exceeds
0.4 mole fraction, and wherein a total volume of segregated
carbides is less than 0.05 mole fraction, segregated carbides being
defined as Fe or Cr-rich boride or carbide meeting the equation:
Fe+Cr>50 wt. %, wherein the segregated carbides are
thermodynamically stable at a temperature above a temperature at
which austenite of the alloy is thermodynamically stable.
[0029] In some embodiments, the alloy can be an iron based alloy
and can comprise C: 2.2-4.02 wt. %, and Cr: 10-34 wt. %. In some
embodiments, the alloy can comprise C: 2.5-3.8 wt. %, Cr: 10-28 wt.
%, Nb: 0-5 wt. %, and W: 0-9 wt. %. In some embodiments, the alloy
can comprise Mn: 0-1 wt. %, Mo: 0-1 wt. %, Si: 0-1 wt. %, Ti: 0-0.5
wt. %, and V: 0-3 wt. %.
[0030] In some embodiments, the alloy can comprise C: 2.2-4.02 wt.
%, Cr: 12.7-34 wt. %, Nb: 3.8-5 wt. %, and W: 4.37-9 wt. %.
[0031] In some embodiments, the total carbide and/or boride content
can exceed 0.45 mole fraction. In some embodiments, the total
carbide and/or boride content can exceed 0.50 mole fraction. In
some embodiments, the article of manufacture can comprise a sleeve
or layer used in pipelines designed to carry abrasive slurries.
Also disclosed herein are embodiments of a wear resistant component
which can comprise embodiments of the disclosed article of
manufacture.
[0032] Also disclosed herein are embodiments of a method of forming
a component comprising providing an alloy comprising Fe, Cr, and C,
wherein a total carbide and boride content in a microstructure of
the alloy exceeds 40 volume %. and wherein a grain size of all
carbides and borides is less than or equal to 50 micrometers in
their longest dimension, and forming a component from the
alloy.
[0033] In some embodiments, the alloy can be an iron-based alloy
and can comprise C: 2.2-4.02 wt. %, and Cr: 10-34 wt. %. In some
embodiments, the alloy can comprise C: 2.5-3.8 wt. %, Cr: 10-28 wt.
%, Nb: 0-5 wt. %, W: 0-9 wt. %, Mn: 0-1 wt. %, Mo: 0-1 wt. %, Si:
0-1 wt. %, Ti: 0-0.5 wt. %, and V: 0-3 wt. %. In some embodiments,
the alloy can comprise C: 2.2-4.02 wt. %, Cr: 12.7-34 wt. %, Nb:
3.8-5 wt. %, and W: 4.37-9 wt. %.
[0034] In some embodiments, the total carbide and/or boride content
can exceed 0.45 mole fraction. In some embodiments, the total
carbide and/or boride content can exceed 0.50 mole fraction.
[0035] In some embodiments, the method can comprise forming the
component via a casting process. In some embodiments, the method
can comprise forming the component into a sleeve or layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] FIG. 1 illustrates a solidification diagram of an embodiment
of, in wt. %, Fe: bal, Cr: 25%, C:3.6%.
[0037] FIG. 2 illustrates a solidification diagram of an embodiment
of, in weight %, Fe: 17%, C:3.6%, Nb 5%, W 5%.
[0038] FIGS. 3A-B illustrate an SEM micrograph of embodiments of
alloy X22 at 1,000.times. magnification (FIG. 3A) and 5,000.times.
magnification (FIG. 3B).
[0039] FIG. 4 illustrates an SEM micrograph of embodiments of alloy
X24 at 1,000.times. magnification.
DETAILED DESCRIPTION
[0040] Disclosed herein is an alloy material, such as an alloy
containing Fe, C and Cr, having high carbide contents, as well as a
method of increasing carbide content in an alloy. Generally as
either Cr or C is increased, the alloy is pushed towards increased
amounts of primary, or eutectic, chromium carbide fractions, so
embodiments of the disclosed alloys may fall within the group known
as chromium white irons. In some embodiments, the disclosed alloys
can be "iron based," indicating that they have a composition that
is predominantly iron, e.g., at least 50 wt. % iron. Also disclosed
herein are different criteria that can be used for producing a high
carbide content alloy. Thermodynamic, microstructural, and
compositional criteria could be used to produce such an alloy. In
some embodiments, only one of the criterial can be used to form the
alloy, and in some embodiments multiple criteria can be used to
form the alloy.
Thermodynamic Criteria:
[0041] In some embodiments, an alloy can be described fully by
thermodynamic models. Two thermodynamic criteria can be used to
define fine-grained high carbide content cast irons as are
described herein: 1) the maximum mole fraction of the carbide or
boride content in the material formed during cooling from a liquid
state, and 2) the mole fraction of Fe,Cr-rich type carbides formed
prior to the initial formation of the austenitic or ferritic
matrix.
[0042] Fe,Cr-rich type carbides are defined as those where the
Fe+Cr weight percent exceeds 50% (or exceeds about 50%). An example
solidification diagram is shown in FIG. 1 that demonstrates
embodiments of the thermodynamic criteria described in this
disclosure. As shown in FIG. 1, three phases can exist in the
temperature range shown, Liquid, FCC_A1 (austenite), and
M.sub.7C.sub.3. The maximum mole fraction of carbide as shown on
this plot can be 45% (or about 45%). The mole fraction of
M.sub.7C.sub.3 type carbide which forms prior to the formation of
the austenite can be 9% (or about 9%), and thus can be defined as
segregated carbides. FIG. 1 shows an example within the Fe--Cr--C
system where the total carbide content in the system may not exceed
40% (or about 40%) without introducing undesirable segregated
M.sub.7C.sub.3 type carbides. FIG. 2 shows an example of an alloy
system which can possess a high total carbide content (50-55% mole
fraction or about 50 to about 55% mole fraction) that may not have
any Fe,Cr-rich type carbide phase which forms above the liquidus
temperature of the austenite. As will be described, the alloy shown
as an example in FIG. 2 can possess the disclosed thermodynamic
criteria.
[0043] The first thermodynamic criterion (the maximum mole fraction
of the carbide or boride content in the material formed during
cooling from a liquid state) can be used as an indicator for the
wear resistance of the material. The criterion will be abbreviated
as carbide-max. Generally, increased carbide or boride contents can
lead to increased wear resistance and can be desirable. The maximum
mole fraction of the carbide or boride content can be calculated by
evaluating the phase fractions of thermodynamically stable phases
as a function of temperature over a range from room temperature to
a temperature where the alloy is thermodynamically 100% liquid. The
maximum content of carbides or borides at any one temperature is
defined as carbide-max. Carbide-max, however, can be the sum of all
types of carbide or boride phases at that temperature. In some
embodiments, the carbide-max can be at least 41% (or at least about
41%) mole fraction. In some embodiments, carbide-max can be at
least 45% (or at least about 45%) mole fraction. In some
embodiments, carbide-max can be at least 50% (or at least about
50%) mole fraction.
[0044] The second thermodynamic criterion (the mole fraction of
Fe,Cr-rich type carbides formed prior to the initial formation of
the austenitic or ferritic matrix) can be used as an indicator for
the toughness of the material. The criterion will be abbreviated as
segregated carbide fraction. Generally, an increased mole fraction
of segregated carbides can decrease the toughness of the material
and can be undesirable. The segregated carbide fraction is
calculated by 1) identifying the highest temperature at which an
iron matrix phase (austenite or ferrite) exists; and 2) calculating
the total mole fraction of M.sub.7C.sub.3 type carbides at 5K
higher. In some embodiments, the segregated carbide content can be
below 5% (or below about 5%). In some embodiments, the segregated
carbide content can be 0% (or about 0%).
[0045] Further, in some embodiments, it may be advantageous for the
alloy to have an increased resistance to corrosion. In such
embodiments, an additional thermodynamic criterion can be utilized.
This third criterion can be the chromium content in the Fe-based
matrix phase, whether austenite or ferrite, at 1300K (or about
1300K). This criterion is thereby designated the matrix chromium
content. This value has been selected as it can be similar to the
value measured in casting experiments for several candidate alloys.
In some embodiments, the matrix chromium content can be above 5
weight % (or above about 5 weight %). In some embodiments, the
matrix chromium content can be above 9 weight % (or above about 9
weight %). In some embodiments, the matrix chromium content can be
above 12 weight % (or above about 12 weight %).
[0046] Table 1 below contains a list of some, but not all, alloys
which can meet the thermodynamic criteria.
TABLE-US-00001 TABLE 1 Alloys Which Meet Thermodynamic Criteria Cr
in Total Primary No C Cr Fe Mn Mo Nb Ni Si Ti V W Matrix Carbide
CrC M1 3.4 15 69.6 0 0 5 0 0 0 0 7 5.0% 53.7% 0.0% M2 3.4 15 67.6 0
0 5 0 0 0 0 9 4.9% 56.9% 0.6% M3 3.4 16 68.6 0 0 5 0 0 0 0 7 5.3%
53.8% 0.0% M4 3.4 16 66.6 0 0 5 0 0 0 0 9 5.2% 57.4% 4.1% M5 3.4 17
67.6 0 0 5 0 0 0 0 7 5.7% 54.1% 0.0% M6 3.4 18 66.6 0 0 5 0 0 0 0 7
6.1% 54.6% 1.6% M7 3.4 19 65.6 0 0 5 0 0 0 0 7 6.5% 55.1% 4.5% M8
3.4 20 64.6 0 0 5 0 0 0 0 7 6.9% 55.7% 5.0% M9 3.5 15 69.5 0 0 5 0
0 0 0 7 4.8% 55.0% 0.0% M10 3.5 15 67.5 0 0 5 0 0 0 0 9 4.7% 58.8%
4.0% M11 3.5 16 68.5 0 0 5 0 0 0 0 7 5.1% 55.1% 0.0% M12 3.5 17
67.5 0 0 5 0 0 0 0 7 5.5% 55.3% 1.8% M13 3.5 18 66.5 0 0 5 0 0 0 0
7 5.8% 55.6% 2.6% M14 3.5 20 66.5 0 0 5 0 0 0 0 5 6.7% 50.5% 1.3%
M15 3.6 15 69.4 0 0 5 0 0 0 0 7 4.6% 56.3% 0.8% M16 3.6 15 67.4 0 0
5 0 0 0 0 9 4.6% 60.7% 5.0% M17 3.6 16 68.4 0 0 5 0 0 0 0 7 4.9%
56.3% 1.8% M18 3.6 17 69.4 0 0 5 0 0 0 0 5 5.2% 50.1% 0.5% M19 3.6
17 67.4 0 0 5 0 0 0 0 7 5.3% 56.4% 2.6% M20 3.6 18 68.4 0 0 5 0 0 0
0 5 5.6% 50.5% 1.0% M21 3.6 19 67.4 0 0 5 0 0 0 0 5 6.0% 50.9% 2.4%
M22 3.6 20 66.4 0 0 5 0 0 0 0 5 6.4% 51.5% 3.8% M23 3.7 15 71.3 0 0
5 0 0 0 0 5 4.4% 50.8% 0.0% M24 3.7 15 69.3 0 0 5 0 0 0 0 7 4.5%
57.7% 1.4% M25 3.7 16 70.3 0 0 5 0 0 0 0 5 4.7% 50.9% 1.2% M26 3.7
16 68.3 0 0 5 0 0 0 0 7 4.8% 57.6% 2.2% M27 3.7 17 69.3 0 0 5 0 0 0
0 5 5.0% 51.2% 1.8% M28 3.7 18 68.3 0 0 5 0 0 0 0 5 5.4% 51.5% 3.4%
M29 3.7 19 67.3 0 0 5 0 0 0 0 5 5.8% 51.9% 3.8% M30 3.8 15 71.2 0 0
5 0 0 0 0 5 4.3% 52.1% 1.6% M31 3.8 15 69.2 0 0 5 0 0 0 0 7 4.3%
59.2% 2.7% M32 3.8 16 70.2 0 0 5 0 0 0 0 5 4.5% 52.1% 2.5% M33 3.8
17 69.2 0 0 5 0 0 0 0 5 4.9% 52.3% 3.1% M34 3.8 18 68.2 0 0 5 0 0 0
0 5 5.2% 52.6% 4.7% M35 3.4 21 65.6 0 0 5 0 0 0 0 5 7.4% 50.4% 1.1%
M36 3.4 22 64.6 0 0 5 0 0 0 0 5 7.9% 51.1% 2.4% M37 3.4 23 63.6 0 0
5 0 0 0 0 5 8.4% 52.0% 4.8% M38 3.5 21 65.5 0 0 5 0 0 0 0 5 7.1%
51.2% 2.6% M39 3.5 22 64.5 0 0 5 0 0 0 0 5 7.6% 51.9% 3.8% M40 3.6
21 65.4 0 0 5 0 0 0 0 5 6.8% 52.1% 4.0% M41 3 21 64 0 0 5 0 0 0 0 7
8.5% 51.1% 1.0% M42 3 21 62 0 0 5 0 0 0 0 9 8.4% 52.4% 4.9% M43 3
22 63 0 0 5 0 0 0 0 7 9.0% 51.5% 1.2% M44 3 23 62 0 0 5 0 0 0 0 7
9.6% 51.8% 3.5% M45 3 24 63 0 0 5 0 0 0 0 5 10.1% 50.9% 0.9% M46 3
25 62 0 0 5 0 0 0 0 5 10.7% 51.2% 2.9% M47 3 26 61 0 0 5 0 0 0 0 5
11.3% 51.5% 4.8% M48 3 10 82 1 1 0.5 1 1 0.5 0 0 3.1% 100.0% 0.0%
M49 3 10 81 1 1 0.5 2 1 0.5 0 0 3.0% 100.0% 0.0% M50 3 10 80 1 1
0.5 3 1 0.5 0 0 2.9% 100.0% 0.0% M51 3.5 10 80.5 1 1 0.5 2 1 0.5 0
0 2.6% 100.0% 0.0% M52 3.5 10 79.5 1 1 0.5 3 1 0.5 0 0 2.5% 100.0%
0.0% M53 3.5 11 80.5 1 1 0.5 1 1 0.5 0 0 2.9% 100.0% 0.0% M54 3.5
11 78.5 1 1 0.5 3 1 0.5 0 0 2.7% 100.0% 1.3% M55 3.5 11 77.5 1 1
0.5 4 1 0.5 0 0 2.6% 100.0% 1.6% M56 3.5 12 79.5 1 1 0.5 1 1 0.5 0
0 3.1% 100.0% 1.4% M57 3.5 12 78.5 1 1 0.5 2 1 0.5 0 0 3.0% 100.0%
1.8% M58 3.5 12 77.5 1 1 0.5 3 1 0.5 0 0 2.9% 100.0% 2.8% M59 3.5
13 78.5 1 1 0.5 1 1 0.5 0 0 3.4% 100.0% 2.8% M60 2.5 23 62.5 0 0 0
0 0 0 3 9 8.3% 50.2% 2.5% M61 2.5 24 61.5 0 0 0 0 0 0 3 9 8.9%
50.4% 5.0% M62 2.5 25 61.5 0 0 0 0 0 0 3 8 9.5% 50.2% 4.8% M63 2.5
27 60.5 0 0 0 0 0 0 3 7 10.9% 50.1% 4.6% M64 2.5 28 59.5 0 0 0 0 0
0 3 7 11.6% 50.2% 4.9% M65 2.6 23 67.4 0 0 0 0 0 0 0 7 8.6% 50.1%
0.9% M66 2.6 23 66.4 0 0 0 0 0 0 0 8 8.5% 50.7% 4.1% M67 2.6 23
65.4 0 0 0 0 0 0 1 8 8.3% 51.0% 3.5% M68 2.6 23 64.4 0 0 0 0 0 0 2
8 8.1% 50.9% 3.1% M69 2.6 23 63.4 0 0 0 0 0 0 3 8 8.0% 50.5% 2.8%
M70 2.6 23 63.4 0 0 1 0 0 0 2 8 8.6% 50.0% 2.8% M71 2.6 23 62.4 0 0
1 0 0 0 3 8 8.5% 50.2% 2.8% M72 2.6 24 66.4 0 0 0 0 0 0 0 7 9.0%
50.4% 3.2% M73 2.6 24 65.4 0 0 0 0 0 0 1 7 8.8% 50.7% 2.8% M74 2.6
24 64.4 0 0 0 0 0 0 1 8 8.8% 51.3% 3.8% M75 2.6 24 64.4 0 0 0 0 0 0
2 7 8.7% 50.3% 2.6% M76 2.6 24 63.4 0 0 0 0 0 0 2 8 8.6% 51.5% 3.5%
M77 2.6 24 63.4 0 0 0 0 0 0 3 7 8.7% 50.1% 0.5% M78 2.6 24 62.4 0 0
0 0 0 0 3 8 8.5% 51.7% 3.4% M79 2.6 25 66.4 0 0 0 0 0 0 0 6 9.6%
50.1% 2.0% M80 2.6 25 64.4 0 0 0 0 0 0 1 7 9.4% 50.9% 3.0% M81 2.6
25 63.4 0 0 0 0 0 0 2 7 9.2% 51.2% 2.9% M82 2.6 25 62.4 0 0 0 0 0 0
3 7 9.1% 51.4% 3.0% M83 2.6 25 62.4 0 0 1 0 0 0 2 7 9.8% 50.1% 4.7%
M84 2.6 25 61.4 0 0 1 0 0 0 3 7 9.8% 50.2% 4.8% M85 2.6 26 65.4 0 0
0 0 0 0 0 6 10.1% 50.3% 4.1% M86 2.6 26 64.4 0 0 0 0 0 0 1 6 9.9%
50.6% 4.1% M87 2.6 26 63.4 0 0 0 0 0 0 2 6 9.8% 50.9% 2.1% M88 2.6
26 62.4 0 0 0 0 0 0 3 6 9.7% 51.2% 2.3% M89 2.6 27 65.4 0 0 0 0 0 0
0 5 10.6% 50.0% 2.5% M90 2.6 27 64.4 0 0 0 0 0 0 1 5 10.5% 50.3%
2.8% M91 2.6 27 63.4 0 0 0 0 0 0 1 6 10.5% 50.9% 4.2% M92 2.6 27
63.4 0 0 0 0 0 0 2 5 10.4% 50.6% 0.9% M93 2.6 27 62.4 0 0 0 0 0 0 2
6 10.4% 51.1% 4.4% M94 2.6 27 62.4 0 0 0 0 0 0 3 5 10.4% 50.9% 1.3%
M95 2.6 27 61.4 0 0 0 0 0 0 3 6 10.4% 51.4% 4.6% M96 2.6 27 60.4 0
0 0 1 0 0 3 6 11.1% 50.2% 4.5% M97 2.6 28 64.4 0 0 0 0 0 0 0 5
11.2% 50.3% 4.5% M98 2.6 28 63.4 0 0 0 0 0 0 1 5 11.1% 50.6% 4.9%
M99 2.6 28 63.4 0 0 0 0 0 0 2 4 11.0% 50.3% 1.5% M100 2.6 28 62.4 0
0 0 0 0 0 2 5 11.0% 50.8% 3.1% M101 2.6 28 62.4 0 0 0 0 0 0 3 4
11.0% 50.6% 0.0% M102 2.6 28 61.4 0 0 0 0 0 0 3 5 11.0% 51.1% 3.6%
M103 2.6 28 60.4 0 0 0 0 0 0 3 6 11.1% 51.6% 4.9% M104 2.6 28 59.4
0 0 0 1 0 0 3 6 11.8% 50.4% 4.8%
Microstructural Criteria:
[0047] In some embodiments, the alloy can be described by the
microstructural features it possesses. Similar to the concepts
described as the thermodynamic criteria, it can be advantageous to
have a high fraction of carbides (40% volume fraction or higher, or
about 40% volume fraction or higher) to increase hardness and wear
resistance. For example, embodiments of the disclosed alloys can
have a hardness between 55-70 HRC (or between about 50 and about 70
HRC). In some embodiments, the disclosed alloys can have a hardness
between 60-65 HRC (or between about 60 and about 65 HRC). In some
embodiments, the disclosed alloys can have high abrasion resistance
as classified by ASTM 65 testing of at least below 0.2 grams lost
(or below about 0.2 grams lost). In some embodiments, the disclosed
alloys can have high abrasion resistance as classified by ASTM 65
testing of at least below 0.15 grams lost (or below about 0.15
grams lost). In some embodiments, the disclosed alloys can have
high abrasion resistance as classified by ASTM 65 testing of at
least below 0.2 grams lost (or below about 0.2 grams lost).
However, it can be also advantageous for these carbides to be
relatively fine-grained in order for the structure to maintain a
minimum toughness.
[0048] In some embodiments, the measured volume fraction of the
carbides or borides in the alloy can exceed 40 volume % (or exceed
about 40 volume %). In some embodiments, the measured volume
fraction of the carbides can exceed 45 volume % (or exceed about 45
volume %). In some embodiments, the measured volume fraction in the
alloy can exceed 50 volume % (or exceed about 50 volume %).
[0049] In some embodiments, the grain size of any carbides and
borides present in the microstructure may not exceed 50 micrometers
(or exceed about 50 micrometers) in their longest dimension. In
some embodiments, the grain of any carbides and borides present in
the microstructure may not exceed 25 micrometers (or exceed about
25 micrometers) in their longest dimension. In some embodiments,
the grain of any carbides and borides present in the microstructure
may not exceed 5 micrometers (or exceed about 5 micrometers) in
their longest dimension. In some embodiments, all carbides and
borides are below the above listed parameters. In some embodiments,
substantially all carbides and borides are below the above listed
parameters. In some embodiments, 90%, 95%, 98%, or 99% of all
carbides and borides are below the above listed parameters.
[0050] An example of a candidate microstructure which meets the
above specified criteria is alloy X22 as shown in FIGS. 3A-B. The
SEM micrograph shows a material with a very high fraction of
carbides with a fine-grain size. Two types of carbide dominate the
microstructure, niobium carbide (301) and chromium carbide (302).
Generally, in alloys with excess carbide content, commonly done
through increasing the carbon above the eutectic point, the
chromium carbide can become coarse. However, as demonstrated in
this example, the chromium carbides remain fine on the order of
10.mu..times.1-2.mu. in dimension.
[0051] As previously mentioned, the formation of a high fraction of
fine-grained chromium carbides is not an inherent feature of this
alloy system as demonstrated by the micrograph shown in FIG. 4. The
X24 alloy has a relatively similar composition to X22, however the
microstructure possesses larger chromium carbides (401) on the
order of 50-150 .mu.m known to reduce toughness. This example is
provided to illustrate the fact that simple alloying additions of
carbide forming elements such as Nb, Ti, W, Mo, V, W, and/or Ta are
not sufficient to produce the microstructural features described in
this disclosure. Rather, relatively small compositional spaces
exist within the greater region defined as cast irons, and
computational modeling is the only effective mechanism to
effectively identify this space.
[0052] Based on scanning electron microscopy the alloy compositions
which possessed the defined microstructural criteria include X21
and X22.
TABLE-US-00002 TABLE 2 Experimental Alloy Chemistries Produced in
Ingot Form Alloys B C Cr Cu Fe M n Mo Nb Ni Si Ti V W X1 0.0 2.0
24.0 1.2 63.8 2.0 3.0 0.0 2.5 1.5 0.0 0.0 0.0 X2 0.0 2.0 24.0 1.2
61.8 2.0 3.0 2.0 2.5 1.5 0.0 0.0 0.0 X3 0.0 2.0 24.0 1.2 60.3 2.0
3.0 3.0 2.5 1.5 0.5 0.0 0.0 X4 0.0 2.0 24.0 1.2 55.8 2.0 3.0 4.0
2.5 1.5 4.0 0.0 0.0 X5 1.0 2.0 24.0 1.2 58.8 2.0 3.0 2.0 2.5 1.5
2.0 0.0 0.0 X6 0.5 2.0 24.0 1.2 61.3 2.0 3.0 2.0 2.5 1.5 0.0 0.0
0.0 X7 2.0 1.0 24.0 1.2 59.3 2.0 3.0 1.5 2.5 1.5 2.0 0.0 0.0 X8 0.0
1.5 24.0 1.2 60.3 2.0 3.0 2.0 2.5 1.5 2.0 0.0 0.0 X9 0.5 1.5 24.0
1.2 61.3 2.0 3.0 1.5 2.5 1.5 1.0 0.0 0.0 X10 1.0 1.0 24.0 1.2 61.8
2.0 3.0 0.5 2.5 1.5 1.5 0.0 0.0 X11 1.5 1.0 24.0 1.2 61.3 2.0 3.0
1.5 2.5 1.5 0.5 0.0 0.0 X12 0.0 3.0 24.0 1.2 59.8 2.0 3.0 2.0 2.5
1.5 1.0 0.0 0.0 X13 0.0 3.0 25.0 1.2 58.8 2.0 3.0 2.0 2.5 1.5 1.0
0.0 0.0 X14 0.0 2.0 24.0 1.2 59.3 2.0 3.0 2.0 2.5 1.5 0.5 0.0 2.0
X15 0.0 2.5 27.0 1.2 52.8 2.0 3.0 2.0 2.5 1.5 0.5 0.0 5.0 X16 0.0
2.5 24.0 1.2 58.8 2.0 3.0 2.0 2.5 1.5 0.5 2.0 0.0 X17 0.0 3.0 24.0
1.2 55.3 2.0 3.0 2.0 2.5 1.5 0.5 5.0 0.0 X18 0.0 3.4 20.0 0.0 66.6
0.0 0.0 5.0 0.0 0.0 0.0 0.0 5.0 X19 0.0 3.6 20.0 0.0 66.4 0.0 0.0
5.0 0.0 0.0 0.0 0.0 5.0 X20 0.0 3.8 20.0 0.0 66.2 0.0 0.0 5.0 0.0
0.0 0.0 0.0 5.0 X21 0.0 3.8 15.0 0.0 71.2 0.0 0.0 5.0 0.0 0.0 0.0
0.0 5.0 X22 0.0 2.6 28.0 0.0 59.4 0.0 0.0 5.0 0.0 0.0 0.0 0.0 5.0
X23 0.0 2.2 24.0 0.0 59.8 0.0 0.0 5.0 0.0 0.0 0.0 0.0 9.0 X24 0.0
3.4 34.0 0.0 52.6 0.0 0.0 5.0 0.0 0.0 0.0 0.0 5.0 X25 0.0 3.8 31.0
0.0 55.2 0.0 0.0 5.0 0.0 0.0 0.0 0.0 5.0 X26 0.0 3.8 32.0 0.0 48.2
0.0 0.0 5.0 0.0 0.0 0.0 0.0 11.0 X27 0.0 3.8 32.0 0.0 44.2 0.0 0.0
5.0 0.0 0.0 0.0 0.0 15.0
TABLE-US-00003 TABLE 3 Measured Alloy Chemistries, via Glow
Discharge Spectrometry, for Selected Experimental Ingots Alloys B C
Cr Cu Fe Mn Mo Nb Ni Si Ti V W X1 0.00 2.29 22.20 1.41 67.8 1.59
0.64 2.52 1.51 0.00 0.00 0.00 X2 0.00 2.37 19.40 1.32 65.9 1.66
2.48 2.38 3.06 1.42 0.00 0.00 0.00 X3 0.00 2.09 22.70 1.23 62.9
1.52 2.62 2.08 3.03 1.31 0.53 0.00 0.00 X4 0.00 1.96 21.10 1.13
55.6 1.37 12.60 1.98 2.94 0.94 0.39 0.00 0.00 X5 0.56 1.97 23.30
1.21 60.3 1.57 3.03 1.57 3.25 1.21 2.06 0.00 0.00 X6 0.28 2.13
22.00 1.27 65.2 1.58 1.33 1.73 3.04 1.43 0.00 0.00 0.00 X7 0.00
2.13 22.50 1.09 59.5 1.21 3.13 2.70 3.28 1.14 3.31 0.00 0.00 X8
1.08 1.08 23.40 1.21 61.2 1.55 2.85 1.24 3.25 1.28 1.87 0.00 0.00
X9 0.00 1.50 22.80 1.10 62.7 1.57 2.84 1.41 2.95 1.20 1.94 0.00
0.00 X10 0.30 1.56 22.40 1.15 63.6 1.62 3.14 1.19 2.89 1.22 0.94
0.00 0.00 X11 0.57 0.99 23.10 1.17 63.4 1.77 3.02 0.47 2.90 1.18
1.39 0.00 0.00 X12 0.84 1.00 22.70 1.21 63.6 1.78 2.70 1.31 3.05
1.25 0.51 0.00 0.00 X13 0.00 3.24 22.10 1.29 62.8 1.37 2.19 1.57
3.15 1.36 0.97 0.00 0.00 X14 0.00 2.96 22.90 1.21 59.7 1.34 5.27
1.44 3.02 1.10 1.03 0.00 0.00 X15 0.00 2.44 21.60 1.19 62.2 1.51
3.11 1.60 2.74 1.28 0.47 0.00 1.81 X16 0.00 3.89 23.50 1.14 57.1
1.38 2.62 1.60 3.17 1.45 0.44 0.00 3.75 X17 0.00 2.64 22.50 1.20
61.5 1.43 2.66 1.54 2.96 1.32 0.51 1.74 0.00 X18 0.00 3.00 22.90
1.27 57.6 1.40 3.37 1.52 3.04 1.27 0.54 4.11 0.00 X19 0.00 4.35
16.20 0.00 69.3 0.73 0.00 3.77 0.30 0.77 0.00 0.00 4.55 X20 0.00
4.32 14.90 0.00 69.3 0.68 0.00 5.21 0.28 0.75 0.00 0.00 4.57 X21
0.00 4.65 16.40 0.00 68.2 0.76 0.00 4.56 0.28 0.81 0.00 0.00 4.34
X22 0.00 4.02 12.70 0.00 73.4 0.73 0.00 3.83 0.24 0.70 0.00 0.00
4.39 X23 0.00 3.13 25.00 0.00 61.5 0.58 0.00 4.47 0.30 0.64 0.00
0.00 4.3 X24 0.00 2.42 21.20 0.00 60.7 0.52 0.00 4.77 0.36 0.52
0.00 0.00 9.49 X25 0.00 3.86 29.10 0.00 56.3 0.65 0.00 4.71 0.35
0.75 0.00 0.00 4.27
Metal Alloy Composition
[0053] In some embodiments, the disclosed alloys can be iron based
alloys having both chromium and carbon in order to form eutectic
chromium carbides. In some embodiments, chromium can be from 10-34
(or about 10 to about 34) wt. % and carbon can be form 2.2-4.02 (or
about 2.2 to about 4.02) wt. %. In some embodiments, the alloy can
be described by a composition in weight percent comprising the
following elemental ranges which can meet certain thermodynamic
criteria, and which are can be at least partially based on the
compositions presented in Table 1 discussed above: [0054] 1. Fe, C:
2.5-3.8%, Cr: 10-28%, Mn: 0-1%, Mo: 0-1%, Nb: 0-5%, Si: 0-1%,
Ti:0-0.5%, V: 0-3%, W: 0-9%; or Fe, C: about 2.5-about 3.8%, Cr:
about 10-about 28%, Mn: about 0-about 1%, Mo: about 0-about 1%, Nb:
about 0-about 5%, Si: about 0-about 1%, Ti: about 0-about 0.5%, V:
about 0-about 3%, W: about 0-about 9%;
[0055] In some embodiments, the alloy can be described by a
composition in weight percent comprising the following elemental
ranges which have been produced and evaluated experimentally, and
which are at least partially based on the compositions presented in
Table 2 and Table 3: [0056] 2. Fe, B: 0-2%, C: 1-3.8%, Cr: 15-34%,
Cu:0-1.2%, Mn: 0-2%, Mo: 0-3%, Nb: 0.5-5%, Si: 0-1.5%, Ni:0-2.5%,
Ti:0-4%, V: 0-5%, W: 0-15%; or Fe, B: about 0-about 2%, C: about
1-about 3.8%, Cr: about 15-about 34%, Cu: about 0-about 1.2%, Mn:
about 0-about 2%, Mo: about 0-about 3%, Nb: about 0.5-about 5%, Si:
about 0-about 1.5%, Ni: about 0-about 2.5%, Ti: about 0-about 4%,
V: about 0-about 5%, W: about 0-about 15%
[0057] In some embodiments, the alloy can be described by a
composition in weight percent comprising the following elemental
ranges which have been produced and evaluated experimentally and
which can meet certain microstructural criteria, and which are at
least partially based on the compositions presented in Table 2 and
Table 3 above: [0058] 3. Fe, C: 2.2-4.02%, Cr: 12.7-34%, Mn:
0-0.73%, Nb: 3.83-5%, Ni:0-0.3%, Si:0-0.7%, W: 4.37-9%; or Fe, C:
about 2.2-about 4.02%, Cr: about 12.7-about 34%, Mn: about 0-about
0.73%, Nb: about 3.83-about 5%, Ni: about 0-about 0.3%, Si: about
0-about 0.7%, W: about 4.37-about 9%.
[0059] In some embodiments, the alloy can be described by a
composition in weight percent comprising the following elemental
ranges as defined through glow discharge spectrometer readings,
which have been produced and evaluated experimentally and which can
meet certain microstructural criteria, and which are at least
partially based on the compositions presented in Table 3 above:
[0060] 4. Fe, C: 3.1-4.02%, Cr: 12.7-25%, Mn: 0.58-0.73%, Nb:
3.83-4.5%, Ni:0.24-0.3%, Si:0.64-0.7%, W: 4.37-9%; or Fe, C: about
3.1-about 4.02%, Cr: about 12.7-about 25%, Mn: about 0.58-about
0.73%, Nb: about 3.83-about 4.5%, Ni: about 0.24-about 0.3%, Si:
about 0.64-about 0.7%, W: about 4.37-about 9%.
[0061] In some embodiments, the alloy can be described by specific
compositions in weight percent comprising the following elements,
which have been produced and evaluated experimentally and which can
meet certain microstructural criteria, and which are at least
partially based on the nominal and measured experimental
compositions: [0062] 5. Fe, C:2.2, Cr:24, Nb: 5, W: 9; or Fe, C:
about 2.2, Cr: about 24, Nb: about 5, W: about 9 [0063] 6. Fe,
C:3.4, Cr:34, Nb: 5, W: 5; or Fe, C: about 3.5, Cr: about 34, Nb:
about 5, W: about 5 [0064] 7. Fe, C:4, Cr:12.7, Mn:0.7, Nb: 3.8,
Ni: 2.4, Si:0.7, W: 4.4; or Fe, C: about 4, Cr: about 12.7, Mn:
about 0.7, Nb: about 3.8, Ni: about 2.4, Si: about 0.7, W: about
4.4 [0065] 8. Fe, C:3.1, Cr:25, Mn:0.6, Nb: 4.5, Ni: 0.3, Si:0.6,
W: 4.4; or Fe, C: about 3.1, Cr: about 25, Mn: about 0.6, Nb: about
4.5, Ni: about 0.3, Si: about 0.6, W: about 4.4
[0066] In some embodiments, the Fe compositions listed above can be
the balance of the alloy material. In some embodiments, minor
impurities can also be found within the composition.
[0067] As an example of embodiments of the above alloys, increased
carbide content can be advantageous because a high fraction of
primary (Nb, Ti, V) carbides can effectively increase the liquidus
temperature of an alloy and decreases fluidity, which can improve
casting processes.
Applications and Processes for Use
[0068] Embodiments of the disclosed alloys can be used in a variety
of applications and industries. Some non-limiting examples of
applications of use include:
[0069] Surface mining applications: Embodiments of the disclosed
alloys can be included in the following components and coatings for
the following components: wear resistant sleeves and/or wear
resistant hardfacing for slurry pipelines, mud pump components
including pump housing or impeller or hardfacing for mud pump
components, ore feed chute components including chute blocks or
hardfacing of chute blocks, separation screens including but not
limited to rotary breaker screens, banana screens, shaker screens,
liners for autogenous grinding mills and semi-autogenous grinding
mills, ground engaging tools and hardfacing for ground engaging
tools, wear plate for buckets and dumptruck liners, heel blocks and
hardfacing for heel blocks on mining shovels, grader blades and
hardfacing for grader blades, stacker reclaimers, siazer crushers,
general wear packages for mining components, and other communition
components.
[0070] Downstream oil and gas applications: Embodiments of the
disclosed alloys can be included in the following components and
coatings for the following components: downhole casing and downhole
casing, drill pipe and coatings for drill pipe including
hardbanding, mud management components, mud motors, fracking pump
sleeves, fracking impellers, fracking blender pumps, stop collars,
drill bits and drill bit components, directional drilling equipment
and coatings for directional drilling equipment including
stabilizers and centralizers, blow out preventers and coatings for
blow out preventers and blow out preventer components including the
shear rams, oil country tubular goods, and coatings for oil country
tubular goods.
[0071] Upstream oil and gas applications: Embodiments of the
disclosed alloys can be included in the following components and
coatings for the following components: process vessels and coating
for process vessels including steam generation equipment, amine
vessels, distillation towers, cyclones, catalytic crackers, general
refinery piping, corrosion under insulation protection, sulfur
recovery units, convection hoods, sour stripper lines, scrubbers,
hydrocarbon drums, and other refinery equipment and vessels.
[0072] Pulp and paper applications: Embodiments of the disclosed
alloys can be included in following components and coatings for the
following components: rolls used in paper machines including yankee
dryers and other dryers, calendar rolls, machine rolls, press
rolls, digesters, pulp mixers, pulpers, pumps, boilers, shredders,
tissue machines, roll and bale handling machines, doctor blades,
evaporators, pulp mills, head boxes, wire parts, press parts, M.G.
cylinders, pope reels, winders, vacuum pumps, deflakers, and other
pulp and paper equipment,
[0073] Power generation applications: Embodiments of the disclosed
alloys can be included in the following components and coatings for
the following components: boiler tubes, precipitators, fireboxes,
turbines, generators, cooling towers, condensers, chutes and
troughs, augers, bag houses, ducts, ID fans, coal piping, and other
power generation components.
[0074] Agriculture applications: Embodiments of the disclosed
alloys can be included in the following components and coatings for
the following components: chutes, base cutter blades, troughs,
primary fan blades, secondary fan blades, augers, and other
agricultural applications.
[0075] Construction applications: Embodiments of the disclosed
alloys can be included in the following components and coatings for
the following components: cement chutes, cement piping, bag houses,
mixing equipment, and other construction applications
[0076] Machine element applications: Embodiments of the disclosed
alloys can be included in the following components and coatings for
the following components: shaft journals, paper rolls, gear boxes,
drive rollers, impellers, general reclamation and dimensional
restoration applications, and other machine element
applications
[0077] Steel applications: Embodiments of the disclosed alloys can
be included in the following components and coatings for the
following components: cold rolling mills, hot rolling mills, wire
rod mills, galvanizing lines, continue pickling lines, continuous
casting rolls and other steel mill rolls, and other steel
applications.
[0078] Further, embodiments of the alloys described can be produced
and or deposited in a variety of techniques effectively. Some
non-limiting examples of processes include:
[0079] Thermal spray process, including those using a wire
feedstock such as twin wire arc, spray, high velocity arc spray,
combustion spray and those using a powder feedstock such as high
velocity oxygen fuel, high velocity air spray, plasma spray,
detonation gun spray, and cold spray. Wire feedstock can be in the
form of a metal core wire, solid wire, or flux core wire. Powder
feedstock can be either a single homogenous alloy or a combination
of multiple alloy powder which result in the desired chemistry when
melted together.
[0080] Welding processes, including those using a wire feedstock
including but not limited to metal inert gas (MIG) welding,
tungsten inert gas (TIG) welding, arc welding, submerged arc
welding, open arc welding, bulk welding, laser cladding, and those
using a powder feedstock including but not limited to laser
cladding and plasma transferred arc welding. Wire feedstock can be
in the form of a metal core wire, solid wire, or flux core wire.
Powder feedstock can be either a single homogenous alloy or a
combination of multiple alloy powder which result in the desired
chemistry when melted together.
[0081] Casting processes, including processes typical to producing
cast iron including but not limited to sand casting, permanent mold
casting, chill casting, investment casting, lost foam casting, die
casting, centrifugal casting, glass casting, slip casting and
process typical to producing wrought steel products including
continuous casting processes.
[0082] Post processing techniques, including but not limited to
rolling, forging, surface treatments such as carburizing,
nitriding, carbonitriding, heat treatments including but not
limited to austenitizing, normalizing, annealing, stress relieving,
tempering, aging, quenching, cryogenic treatments, flame hardening,
induction hardening, differential hardening, case hardening,
decarburization, machining, grinding, cold working, work hardening,
and welding.
[0083] From the foregoing description, it will be appreciated that
an inventive material and methods of manufacturing are disclosed.
While several components, techniques and aspects have been
described with a certain degree of particularity, it is manifest
that many changes can be made in the specific designs,
constructions and methodology herein above described without
departing from the spirit and scope of this disclosure.
[0084] Certain features that are described in this disclosure in
the context of separate implementations can also be implemented in
combination in a single implementation. Conversely, various
features that are described in the context of a single
implementation can also be implemented in multiple implementations
separately or in any suitable subcombination. Moreover, although
features may be described above as acting in certain combinations,
one or more features from a claimed combination can, in some cases,
be excised from the combination, and the combination may be claimed
as any subcombination or variation of any subcombination.
[0085] Moreover, while methods may be depicted in the drawings or
described in the specification in a particular order, such methods
need not be performed in the particular order shown or in
sequential order, and that all methods need not be performed, to
achieve desirable results. Other methods that are not depicted or
described can be incorporated in the example methods and processes.
For example, one or more additional methods can be performed
before, after, simultaneously, or between any of the described
methods. Further, the methods may be rearranged or reordered in
other implementations. Also, the separation of various system
components in the implementations described above should not be
understood as requiring such separation in all implementations, and
it should be understood that the described components and systems
can generally be integrated together in a single product or
packaged into multiple products. Additionally, other
implementations are within the scope of this disclosure.
[0086] Conditional language, such as "can," "could," "might," or
"may," unless specifically stated otherwise, or otherwise
understood within the context as used, is generally intended to
convey that certain embodiments include or do not include, certain
features, elements, and/or steps. Thus, such conditional language
is not generally intended to imply that features, elements, and/or
steps are in any way required for one or more embodiments.
[0087] Conjunctive language such as the phrase "at least one of X,
Y, and Z," unless specifically stated otherwise, is otherwise
understood with the context as used in general to convey that an
item, term, etc. may be either X, Y, or Z. Thus, such conjunctive
language is not generally intended to imply that certain
embodiments require the presence of at least one of X, at least one
of Y, and at least one of Z.
[0088] Language of degree used herein, such as the terms
"approximately," "about," "generally," and "substantially" as used
herein represent a value, amount, or characteristic close to the
stated value, amount, or characteristic that still performs a
desired function or achieves a desired result. For example, the
terms "approximately", "about", "generally," and "substantially"
may refer to an amount that is within less than or equal to 10% of,
within less than or equal to 5% of, within less than or equal to 1%
of, within less than or equal to 0.1% of, and within less than or
equal to 0.01% of the stated amount.
[0089] Some embodiments have been described in connection with the
accompanying drawings. The figures are drawn to scale, but such
scale should not be limiting, since dimensions and proportions
other than what are shown are contemplated and are within the scope
of the disclosed inventions. Distances, angles, etc. are merely
illustrative and do not necessarily bear an exact relationship to
actual dimensions and layout of the devices illustrated. Components
can be added, removed, and/or rearranged. Further, the disclosure
herein of any particular feature, aspect, method, property,
characteristic, quality, attribute, element, or the like in
connection with various embodiments can be used in all other
embodiments set forth herein. Additionally, it will be recognized
that any methods described herein may be practiced using any device
suitable for performing the recited steps.
[0090] While a number of embodiments and variations thereof have
been described in detail, other modifications and methods of using
the same will be apparent to those of skill in the art.
Accordingly, it should be understood that various applications,
modifications, materials, and substitutions can be made of
equivalents without departing from the unique and inventive
disclosure herein or the scope of the claims.
* * * * *