CA1054401A - Metallurgical composition embodying hard metal carbides, and method of making - Google Patents
Metallurgical composition embodying hard metal carbides, and method of makingInfo
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- CA1054401A CA1054401A CA232252A CA232252A CA1054401A CA 1054401 A CA1054401 A CA 1054401A CA 232252 A CA232252 A CA 232252A CA 232252 A CA232252 A CA 232252A CA 1054401 A CA1054401 A CA 1054401A
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Abstract
ABSTRACT OF THE DISCLOSURE
A hard wear resistant metallurgical composition which in general is a combination of tungsten, titanium, nickel and carbon and may include other elements such as chromium. In preparing the composition, tungsten carbide is admixed by milling with nickel and titanium and subsequently sintered.
The titanium may react with carbon from the tungsten carbide and the released tungsten may alloy with nickel to form a tough binder. The characteristics of the end product may be tailored by controlling the proportions of the various components of the composition including adjustment of the amount of titanium added to the mixture. By this control, the end product may be made magnetic or non-magnetic without losing desirable.
characteristics of strength, hardness and wear resistance.
A hard wear resistant metallurgical composition which in general is a combination of tungsten, titanium, nickel and carbon and may include other elements such as chromium. In preparing the composition, tungsten carbide is admixed by milling with nickel and titanium and subsequently sintered.
The titanium may react with carbon from the tungsten carbide and the released tungsten may alloy with nickel to form a tough binder. The characteristics of the end product may be tailored by controlling the proportions of the various components of the composition including adjustment of the amount of titanium added to the mixture. By this control, the end product may be made magnetic or non-magnetic without losing desirable.
characteristics of strength, hardness and wear resistance.
Description
1 05 ~
The present invention relates to metallurgical compositions embodying metal carbides, in particular, hard metal carbides, and is especially concerned with a composition that can be tailored as to characteristics including that of being nonmagnetic or magnetic while remaîning hard and wear resistant.
Many hard wear resistant metallurgical compositions embody-ing hard metal carbides are known, and most thereof are quite satisfactory for the intended use. An application for hard wear resistant carbide materials in connection with which there has not, heretofore, been satisfactory materials are those uses in which the hard wear resistant material must be nonmagnetic.
For example, machines in which magnetic tapes are employed often require wear resistant guides and the like for supporting and guiding the tapes. Still other cases will suggest themselves in which a hard wear resistant, or structurally strong, member is required where magnetic interactions are undesirable and in these cases, also, nonmagnetic carbide materials would be highly useful.
While the metallurgical composition according to the present invention can, as will be shown, be made nonmagnetic, magnetic variations of the composition have also been found highly useful in places where the composition must be hard and wear resistant and/or noncorrosive and/or noncontaminating or where the material must be extremely hard as in connection with a tool -. . , ,, :.
composltlon O
With the foregoing in mind, a primary objective of the present invention is the provision of a metallurgical composition 1~ 5 ~4~ i embodying hard metal carbides which has the possibility of being formulated so as to be nonmagnetic but which will retain the -desirable attributes o~ hard carbide metallurgical compositions.
Another object is the provision of a metallurgical composi- -tion of the nature referred to which can be so co~pounded prior to the formation thereof as to be either nonmagnetic or magnetic when completed. -A still further object is the provision of a metallurgical composition embodying hard metal carbides which is satisfactory for use as a ~ool and which can be compounded to vary in magnetic properties at room temperature to the state of being nonmagnetic, BRIEF SUMMARY OF THE INVENTION:
The metallurgical composition according to the present -invention is concerned primarily with tungsten, titanium, nickel, ~ -carbon compositions and to which may be added a certain amount of chromium and other carbides. The composition of the present invention can be compounded in such a manner as to be either nonmagnetic or magnetic while still having the desirable charac-teristics of hard wear resistant cemented carbides.
Thus, in accordance with the present teachings, there is provided a sintered cemented carbide product the compositions of which comprises tungsten carbide, titanium carbide and a binder alloy comprising tungsten-nickel in which the ratio o~ the tungsten in the binder alloy to the binder is from 2 to 28 per cent by weight. By one aspect the above product is non-ferro-magnetic and has a ratio of tungsten in the binder alloy to the binder alloy of 15 to 28 per cent by weight. By another aspect - .................. . - . .: :
the above product has ferromagnetic properties and has a ratio of tungsten in the binder alloy to the binder alloy of less than 14 per cent by weight.
The hard metal carbides, including tungsten carbide and titanium carbide, are nonmagnetic so that a metallurgical composi-tion embodying hard metal carbides can be made provided a suitable metal binder system is employed which is also nonmagnetic.
A binder metal for a cemented carbide composition should be tough and should also wet the carbide. A nickel binder system is, thus, a preferred binder because nickel wets the carbide compounds and is tough. Nickel, furthermore, although being itself ferromagnetic, can be alloyed with tungsten, which is also nonmagnetic, without undergoing a phase change upon heating or upon cooling from the liquid phase over a relatively broad alloying range and an alloy of this material can be selected which is nonmagnetic. By nonmagnetic, a material is referred to which has magnetic permeability near unity and which is lacking in the ability to become magnetized or to exhibit induced `~ `
~ . ,: .
magnetism, namely, a material with ~ Oersted coercive force. ~ :
When the more common binder metal, cobalt, is employed as a binder, and the composition is adjusted to be, or to approach ~i being, nonmagnetic, the binder phase of the composition becomes extremely brittle clue to the formation of Co3W3C and the composi-tion is, thus, defective for many uses. The present invention overcomes this objection by including titanium in the composition and employing nickel or nickel and chromium as the basic binder metal.
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When titanium, tungsten carbide and nickel, with or without some chromium, are admixed in powder form, compacted and hea~ed ~ :
so that a liquid phase is formed containing W, C and some or all of the titanium in solution, then the carbon can associate itself with the titanium to form titanium carbide or a solid solution of TiC with WC, or both, because the free energy of formation for forming TiC is more favorable than for forming WC.
Thus, tungsten is freed during sintering to alloy with a binder metal or metals.
The mass balance is calculated so the stoichiometric excess W during sintering can alloy with the nickel and result in a magnetic or nonmagnetic binder alloyO The carbon balance with :
respect to the titanium must take into account the non-stoichio-metric nature of TiC as less than one carbon atom per titanium atom is sufficient to form titanium carbide. --4a-. ~
.
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Thus, by including titanium in the mixture, carbon is removed from the melt because of the affini-ty of titanium for the carbon, and an alloy of nickel and tungsten and/or titanium is formed during sintering. It has been found that a fairly wide range of compositions according to the present invention will result in the production of a nonmagnetic alloy having the same crystal structure as pure nickel, namely, face centered cubic.
While carbon deficient tungsten carbide can be employed with a nickel binder to yield a nickel-tungsten alloy binder after sintering, extremely close control of the respective levels of nickel and carbon are required and an impractical control situation arises.
It has been found that small, less than 0.5 weight per cent, titanium metal additions as described herein very effectively inhibit grain growth during sintering and result in a Eine grained structure and consequently improved strength.
A particular advantage of the present invention is to be found in the fact that, once the analysis of the WC component is ascertained to reveal the amount of carbon in the WC component, the amount of Ti to add to the composition can readily be calculated. Formulation and control are thus greatly simplified~
The exact nature of the present invention will become more apparent upon reference to the following specification giving specific examples and to the accompanying drawings in which: -Figure 1 is a graph giving weight per cent titanium tocharge.
.. , . . . ~ ~ . .. . . . .. . ... . .
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Figure 2 is a part of the nickel-tungsten phase diagram showing, in particular, the magnetic transformation character-istics of nickel-tungsten alloys.
DETAILED DESCRIPTION OF THE INVENTION:
The compositions according to the present invention can be compounded by closely analyzing each constituent for the carbon, oxygen, nitrogen and metallic impurities. The amount of Ti required to release the quantity of tungsten from the tungsten carbide to produce the nickel-tungsten alloy composition can then be calculated or determined experimentally.
In making the calculations, the tungsten level desired in the binder and the nickel content are established and the equations giving the desired amount of titanium, or tungsten, are solved.
In preparing the compositions, the powders charged in the mixture before sintering have about the following percentages `
by weight: ~-Nickel - 3.0 - 25.0 Titanium - .05 - 2.0 Tungsten Carbide- Balance In addition chromi~m may also be included in the range of 0.0 to 2,0 per cent by weight.
Figure 1 shows how much titanium to charge with tungsten carbide having the indicated total carbon content and negligible oxygen, nitrogen and metallic impuritles. In the graph, the weight % of Ni in the composition is always 10, The other 90%
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: .
~0544~1 , of the composition is made up of WC and Ti. Thus, for example, at 1 wt. % Ti, there will be 89 wt. % WC. Each line of the graph shows ~he amount of Ti to be supplied to obtain the indicated weight % of W in the binder.
TABLE I
Weight % Titanium to charge to a 10 Wt. % Nickel balance tungsten carbide composition (the WC having 6.10 Wt. % carbon `-content and negligible impurities) to obtain the calculated 10, , ' . ' ' ' .
-6a- ~
~05~40~
20, or 25 Wt. % W/(W ~ Ni) in the binder alloy as a function of carburization of the titanium additionO
Est.
Calculated Wt. % Atom Wt. % Wto % Ti to Ratio Nickel W/(~ ~ Ni~ Char~e C/Ti 0.283 0.6 0.240 0O7 0.208 0.8 0O187 0.9 0.879 0.6 0.748 0O7 0.654 0.8 0.585 0O9 1.242 0.6 1.077 0,7 0.940 0.8 0.831 0.9 Chromium metal additions may be made to the composition, as will be explained more fully hereinafter, and help to further `
inhibit grain growth and also to stabilize the nonmagnetic -properties when the composition is to be nonmagnetic. Chromium has produced good results and for a 10 weight % nickel composi-tion, a 1 weight % chromium level produced satisfactory results.
The chromium metal addition is not essential to achieve nonmagnetic properties. It can react with and take up some of the carbon by forming carbides of chromium, and it can also alloy with the hickel.
Titanium can be supplied in the form of powders of titanium metal, any alloy of titanium with nickel, not necessarily TiNi eutetic composition or as a hydride of titanium. The last mentioned form is preferred because it is less reactive than the pure metal and can be milled readily. Also, it is less - ~ .
~05~Ql ,.
expensive than an alloy of titanium with nickel while, urther-more, the hydrogen that is evolved from titanium hydride during the early stagas of sintering can be beneficial because it can be effective for reducing surface oxides, particularly those which form on nickel.
The nonmagnetic capability of the type of composition disclosed herein is important but there are other applications for the composition wherein chemical inertness and strength and wear resistance are the principal characteristics desired.
Nonmagnetic grades of the composition, as mentioned, are particularly useful for magnetic tape guides and the like. Both magnetic and nonmagnetic gradés of the composition are useful as cutting tools and the like and also as tools for use in glass making and the like where cobalt contamination is detrimental, The following chart gives a number of examples of composi-tions, the first five thereof being nonmagnetic grades and the last two being magnetic grades:
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The last two columns of the chart, the first of which gives transverse rupture strength, alld the other of which gives hardness on the Rockwell 'lA" scale, have two values for each composition. The reason for this is that the upper number of each pair is the value obtained when the composition is compacted and vacuum sintered and the second value is for a vacuum sintered speciment subjected to reheating in the presence of a high pressure inert gas.
In making any of the compositions referred to above, con- -ventional milling procedures may be followed. A tungsten carbide lined mill with tungsten carbide milling media therein is preferably employed to avoid contamination. This mixture is milled for about ~ to 15 days and then processed in a conven-tional manner to arrive at a sintered end product.
Sintering may be accomplished at from about 1350 to about 1550 degrees Centigrade for a period of about 0~25 to 2.0 hours at 0.02 to 0.75 Torr.
It will be understood that during sintering tungsten released from tungsten carbide by the capturing of the carbon by titanium, can form what is referred to as Eta phase in com-bination with nickel and carbon~ or if the composition contains chromium, with chromium and carbon.
Such a phase might be represented as Ni3W3C. This material will not, if present in small amounts, detract from the physical or magnetic properties of the material and serves as a part of the binder of the sintered composition.
Modifications may be made within the scope of the appended claims.
.
: , . - .. . . .
The present invention relates to metallurgical compositions embodying metal carbides, in particular, hard metal carbides, and is especially concerned with a composition that can be tailored as to characteristics including that of being nonmagnetic or magnetic while remaîning hard and wear resistant.
Many hard wear resistant metallurgical compositions embody-ing hard metal carbides are known, and most thereof are quite satisfactory for the intended use. An application for hard wear resistant carbide materials in connection with which there has not, heretofore, been satisfactory materials are those uses in which the hard wear resistant material must be nonmagnetic.
For example, machines in which magnetic tapes are employed often require wear resistant guides and the like for supporting and guiding the tapes. Still other cases will suggest themselves in which a hard wear resistant, or structurally strong, member is required where magnetic interactions are undesirable and in these cases, also, nonmagnetic carbide materials would be highly useful.
While the metallurgical composition according to the present invention can, as will be shown, be made nonmagnetic, magnetic variations of the composition have also been found highly useful in places where the composition must be hard and wear resistant and/or noncorrosive and/or noncontaminating or where the material must be extremely hard as in connection with a tool -. . , ,, :.
composltlon O
With the foregoing in mind, a primary objective of the present invention is the provision of a metallurgical composition 1~ 5 ~4~ i embodying hard metal carbides which has the possibility of being formulated so as to be nonmagnetic but which will retain the -desirable attributes o~ hard carbide metallurgical compositions.
Another object is the provision of a metallurgical composi- -tion of the nature referred to which can be so co~pounded prior to the formation thereof as to be either nonmagnetic or magnetic when completed. -A still further object is the provision of a metallurgical composition embodying hard metal carbides which is satisfactory for use as a ~ool and which can be compounded to vary in magnetic properties at room temperature to the state of being nonmagnetic, BRIEF SUMMARY OF THE INVENTION:
The metallurgical composition according to the present -invention is concerned primarily with tungsten, titanium, nickel, ~ -carbon compositions and to which may be added a certain amount of chromium and other carbides. The composition of the present invention can be compounded in such a manner as to be either nonmagnetic or magnetic while still having the desirable charac-teristics of hard wear resistant cemented carbides.
Thus, in accordance with the present teachings, there is provided a sintered cemented carbide product the compositions of which comprises tungsten carbide, titanium carbide and a binder alloy comprising tungsten-nickel in which the ratio o~ the tungsten in the binder alloy to the binder is from 2 to 28 per cent by weight. By one aspect the above product is non-ferro-magnetic and has a ratio of tungsten in the binder alloy to the binder alloy of 15 to 28 per cent by weight. By another aspect - .................. . - . .: :
the above product has ferromagnetic properties and has a ratio of tungsten in the binder alloy to the binder alloy of less than 14 per cent by weight.
The hard metal carbides, including tungsten carbide and titanium carbide, are nonmagnetic so that a metallurgical composi-tion embodying hard metal carbides can be made provided a suitable metal binder system is employed which is also nonmagnetic.
A binder metal for a cemented carbide composition should be tough and should also wet the carbide. A nickel binder system is, thus, a preferred binder because nickel wets the carbide compounds and is tough. Nickel, furthermore, although being itself ferromagnetic, can be alloyed with tungsten, which is also nonmagnetic, without undergoing a phase change upon heating or upon cooling from the liquid phase over a relatively broad alloying range and an alloy of this material can be selected which is nonmagnetic. By nonmagnetic, a material is referred to which has magnetic permeability near unity and which is lacking in the ability to become magnetized or to exhibit induced `~ `
~ . ,: .
magnetism, namely, a material with ~ Oersted coercive force. ~ :
When the more common binder metal, cobalt, is employed as a binder, and the composition is adjusted to be, or to approach ~i being, nonmagnetic, the binder phase of the composition becomes extremely brittle clue to the formation of Co3W3C and the composi-tion is, thus, defective for many uses. The present invention overcomes this objection by including titanium in the composition and employing nickel or nickel and chromium as the basic binder metal.
~ -4-, .:
"., . , , ~ : . . . ~ . . ; . .
When titanium, tungsten carbide and nickel, with or without some chromium, are admixed in powder form, compacted and hea~ed ~ :
so that a liquid phase is formed containing W, C and some or all of the titanium in solution, then the carbon can associate itself with the titanium to form titanium carbide or a solid solution of TiC with WC, or both, because the free energy of formation for forming TiC is more favorable than for forming WC.
Thus, tungsten is freed during sintering to alloy with a binder metal or metals.
The mass balance is calculated so the stoichiometric excess W during sintering can alloy with the nickel and result in a magnetic or nonmagnetic binder alloyO The carbon balance with :
respect to the titanium must take into account the non-stoichio-metric nature of TiC as less than one carbon atom per titanium atom is sufficient to form titanium carbide. --4a-. ~
.
~0 54~
Thus, by including titanium in the mixture, carbon is removed from the melt because of the affini-ty of titanium for the carbon, and an alloy of nickel and tungsten and/or titanium is formed during sintering. It has been found that a fairly wide range of compositions according to the present invention will result in the production of a nonmagnetic alloy having the same crystal structure as pure nickel, namely, face centered cubic.
While carbon deficient tungsten carbide can be employed with a nickel binder to yield a nickel-tungsten alloy binder after sintering, extremely close control of the respective levels of nickel and carbon are required and an impractical control situation arises.
It has been found that small, less than 0.5 weight per cent, titanium metal additions as described herein very effectively inhibit grain growth during sintering and result in a Eine grained structure and consequently improved strength.
A particular advantage of the present invention is to be found in the fact that, once the analysis of the WC component is ascertained to reveal the amount of carbon in the WC component, the amount of Ti to add to the composition can readily be calculated. Formulation and control are thus greatly simplified~
The exact nature of the present invention will become more apparent upon reference to the following specification giving specific examples and to the accompanying drawings in which: -Figure 1 is a graph giving weight per cent titanium tocharge.
.. , . . . ~ ~ . .. . . . .. . ... . .
~O 5 4~ ~
Figure 2 is a part of the nickel-tungsten phase diagram showing, in particular, the magnetic transformation character-istics of nickel-tungsten alloys.
DETAILED DESCRIPTION OF THE INVENTION:
The compositions according to the present invention can be compounded by closely analyzing each constituent for the carbon, oxygen, nitrogen and metallic impurities. The amount of Ti required to release the quantity of tungsten from the tungsten carbide to produce the nickel-tungsten alloy composition can then be calculated or determined experimentally.
In making the calculations, the tungsten level desired in the binder and the nickel content are established and the equations giving the desired amount of titanium, or tungsten, are solved.
In preparing the compositions, the powders charged in the mixture before sintering have about the following percentages `
by weight: ~-Nickel - 3.0 - 25.0 Titanium - .05 - 2.0 Tungsten Carbide- Balance In addition chromi~m may also be included in the range of 0.0 to 2,0 per cent by weight.
Figure 1 shows how much titanium to charge with tungsten carbide having the indicated total carbon content and negligible oxygen, nitrogen and metallic impuritles. In the graph, the weight % of Ni in the composition is always 10, The other 90%
~ -6-'.
: .
~0544~1 , of the composition is made up of WC and Ti. Thus, for example, at 1 wt. % Ti, there will be 89 wt. % WC. Each line of the graph shows ~he amount of Ti to be supplied to obtain the indicated weight % of W in the binder.
TABLE I
Weight % Titanium to charge to a 10 Wt. % Nickel balance tungsten carbide composition (the WC having 6.10 Wt. % carbon `-content and negligible impurities) to obtain the calculated 10, , ' . ' ' ' .
-6a- ~
~05~40~
20, or 25 Wt. % W/(W ~ Ni) in the binder alloy as a function of carburization of the titanium additionO
Est.
Calculated Wt. % Atom Wt. % Wto % Ti to Ratio Nickel W/(~ ~ Ni~ Char~e C/Ti 0.283 0.6 0.240 0O7 0.208 0.8 0O187 0.9 0.879 0.6 0.748 0O7 0.654 0.8 0.585 0O9 1.242 0.6 1.077 0,7 0.940 0.8 0.831 0.9 Chromium metal additions may be made to the composition, as will be explained more fully hereinafter, and help to further `
inhibit grain growth and also to stabilize the nonmagnetic -properties when the composition is to be nonmagnetic. Chromium has produced good results and for a 10 weight % nickel composi-tion, a 1 weight % chromium level produced satisfactory results.
The chromium metal addition is not essential to achieve nonmagnetic properties. It can react with and take up some of the carbon by forming carbides of chromium, and it can also alloy with the hickel.
Titanium can be supplied in the form of powders of titanium metal, any alloy of titanium with nickel, not necessarily TiNi eutetic composition or as a hydride of titanium. The last mentioned form is preferred because it is less reactive than the pure metal and can be milled readily. Also, it is less - ~ .
~05~Ql ,.
expensive than an alloy of titanium with nickel while, urther-more, the hydrogen that is evolved from titanium hydride during the early stagas of sintering can be beneficial because it can be effective for reducing surface oxides, particularly those which form on nickel.
The nonmagnetic capability of the type of composition disclosed herein is important but there are other applications for the composition wherein chemical inertness and strength and wear resistance are the principal characteristics desired.
Nonmagnetic grades of the composition, as mentioned, are particularly useful for magnetic tape guides and the like. Both magnetic and nonmagnetic gradés of the composition are useful as cutting tools and the like and also as tools for use in glass making and the like where cobalt contamination is detrimental, The following chart gives a number of examples of composi-tions, the first five thereof being nonmagnetic grades and the last two being magnetic grades:
. .
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The last two columns of the chart, the first of which gives transverse rupture strength, alld the other of which gives hardness on the Rockwell 'lA" scale, have two values for each composition. The reason for this is that the upper number of each pair is the value obtained when the composition is compacted and vacuum sintered and the second value is for a vacuum sintered speciment subjected to reheating in the presence of a high pressure inert gas.
In making any of the compositions referred to above, con- -ventional milling procedures may be followed. A tungsten carbide lined mill with tungsten carbide milling media therein is preferably employed to avoid contamination. This mixture is milled for about ~ to 15 days and then processed in a conven-tional manner to arrive at a sintered end product.
Sintering may be accomplished at from about 1350 to about 1550 degrees Centigrade for a period of about 0~25 to 2.0 hours at 0.02 to 0.75 Torr.
It will be understood that during sintering tungsten released from tungsten carbide by the capturing of the carbon by titanium, can form what is referred to as Eta phase in com-bination with nickel and carbon~ or if the composition contains chromium, with chromium and carbon.
Such a phase might be represented as Ni3W3C. This material will not, if present in small amounts, detract from the physical or magnetic properties of the material and serves as a part of the binder of the sintered composition.
Modifications may be made within the scope of the appended claims.
.
: , . - .. . . .
Claims (14)
1. A sintered cemented carbide product whose composition comprises tungsten carbide, titanium carbide and a binder alloy comprising tungsten-nickel in which the ratio of the tungsten in the binder alloy to the binder alloy is from 2 to 28 per cent by weight.
2. A product according to Claim 1 that is non-ferromagnetic and has a ratio of tungsten in the binder alloy to the binder alloy of 15 to 28 per cent by weight.
3. A product according to Claim 1 that has ferromagnetic properties and has a ratio of tungsten in the binder alloy to the binder alloy of less than 14 per cent by weight.
4. A product according to Claim 2 in which the powders charged in the mixture before sintering are about the following percentages by weight:
Nickel - 3.0 to 25.0 Titanium - 0.5 to 2.0 Tungsten Carbide - Balance
Nickel - 3.0 to 25.0 Titanium - 0.5 to 2.0 Tungsten Carbide - Balance
5. A product according to Claim 2 in which the binder alloy further includes chromium.
6. A product according to Claim 5 in which the powders are charged in the mixture before sintering in about the follow-ing percentages by weight:
Nickel - 3.0 to 25.0 Titanium - .05 to 2.0 Chromium - 0.0 to 2.0 Tungsten Carbide - Balance
Nickel - 3.0 to 25.0 Titanium - .05 to 2.0 Chromium - 0.0 to 2.0 Tungsten Carbide - Balance
7. A product according to Claim 4 in which the titanium is supplied in the form of titanium hydride.
8. A product according to Claim 4 in which the titanium is supplied in the form of an alloy with at least a portion of the said nickel.
9. A product according to Claim 2 in which the binder alloy further includes un-reacted titanium and the calculated ratio of the tungsten in the binder alloy to the binder alloy is from 15 to 28 per cent by weight.
10. A method of making a sintered carbide product which comprises milling together a mixture comprising a major part tungsten carbide, titanium, about 10 weight per cent nickel, compacting the milled mixture, and sintering the compacted milled mixture to form the product, the said titanium being added to the mixture calculated in an amount to decarburize the tungsten carbide to a degree which will release tungsten to form an alloy with the nickel up to about 28 weight per cent tungsten in the alloy.
11. The method according to Claim 10 which includes adding at least a part of the titanium in the form of an alloy of titanium and nickel.
12. The method according to Claim 10 which includes adding at least a part of the titanium in the form of titanium hydride.
13. The method according to Claim 10 which includes adding about 1 weight per cent chromium to the mixture.
14. The method according to Claim 13 wherein the titanium charged in the starting composition is such that the calculated ratio W/(W + Ni) in weight per cent ranges from about 20 to 28 and the composition is nonmagnetic.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA232252A CA1054401A (en) | 1975-07-25 | 1975-07-25 | Metallurgical composition embodying hard metal carbides, and method of making |
| CA323,323A CA1078225A (en) | 1975-07-25 | 1979-03-13 | Metallurgical composition embodying hard metal carbides, and method of making |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA232252A CA1054401A (en) | 1975-07-25 | 1975-07-25 | Metallurgical composition embodying hard metal carbides, and method of making |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1054401A true CA1054401A (en) | 1979-05-15 |
Family
ID=4103700
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA232252A Expired CA1054401A (en) | 1975-07-25 | 1975-07-25 | Metallurgical composition embodying hard metal carbides, and method of making |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1054401A (en) |
-
1975
- 1975-07-25 CA CA232252A patent/CA1054401A/en not_active Expired
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