CA1134868A - Cemented carbide - Google Patents
Cemented carbideInfo
- Publication number
- CA1134868A CA1134868A CA000308054A CA308054A CA1134868A CA 1134868 A CA1134868 A CA 1134868A CA 000308054 A CA000308054 A CA 000308054A CA 308054 A CA308054 A CA 308054A CA 1134868 A CA1134868 A CA 1134868A
- Authority
- CA
- Canada
- Prior art keywords
- carbonitride
- tungsten
- molybdenum
- metal
- weight
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 229910052751 metal Inorganic materials 0.000 claims abstract description 30
- 239000002184 metal Substances 0.000 claims abstract description 30
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 17
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 17
- 229910052721 tungsten Inorganic materials 0.000 claims abstract description 17
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims abstract description 10
- 239000000463 material Substances 0.000 claims abstract description 10
- 239000011733 molybdenum Substances 0.000 claims abstract description 10
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000010937 tungsten Substances 0.000 claims abstract description 9
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 claims abstract description 9
- 229910052758 niobium Inorganic materials 0.000 claims abstract description 8
- 229910052702 rhenium Inorganic materials 0.000 claims abstract description 8
- 229910052715 tantalum Inorganic materials 0.000 claims abstract description 8
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 8
- 239000011230 binding agent Substances 0.000 claims abstract description 4
- 229910052757 nitrogen Inorganic materials 0.000 claims description 18
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 14
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 12
- 229910052799 carbon Inorganic materials 0.000 claims description 12
- 239000000203 mixture Substances 0.000 claims description 11
- 238000000034 method Methods 0.000 claims description 6
- -1 iron group metals Chemical class 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 3
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 claims description 3
- 229910000640 Fe alloy Inorganic materials 0.000 claims description 2
- 230000015572 biosynthetic process Effects 0.000 claims description 2
- 150000002739 metals Chemical class 0.000 abstract description 7
- 229910045601 alloy Inorganic materials 0.000 abstract description 2
- 239000000956 alloy Substances 0.000 abstract description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract 1
- 230000000737 periodic effect Effects 0.000 abstract 1
- 239000011651 chromium Substances 0.000 description 21
- 239000000047 product Substances 0.000 description 6
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- 239000001257 hydrogen Substances 0.000 description 4
- 229910052739 hydrogen Inorganic materials 0.000 description 4
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 150000001247 metal acetylides Chemical class 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- INZDTEICWPZYJM-UHFFFAOYSA-N 1-(chloromethyl)-4-[4-(chloromethyl)phenyl]benzene Chemical compound C1=CC(CCl)=CC=C1C1=CC=C(CCl)C=C1 INZDTEICWPZYJM-UHFFFAOYSA-N 0.000 description 1
- 235000006696 Catha edulis Nutrition 0.000 description 1
- 240000007681 Catha edulis Species 0.000 description 1
- 229910003178 Mo2C Inorganic materials 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- XAYGUHUYDMLJJV-UHFFFAOYSA-Z decaazanium;dioxido(dioxo)tungsten;hydron;trioxotungsten Chemical compound [H+].[H+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O XAYGUHUYDMLJJV-UHFFFAOYSA-Z 0.000 description 1
- 238000005261 decarburization Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 229910052738 indium Inorganic materials 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- MGRWKWACZDFZJT-UHFFFAOYSA-N molybdenum tungsten Chemical compound [Mo].[W] MGRWKWACZDFZJT-UHFFFAOYSA-N 0.000 description 1
- RHDUVDHGVHBHCL-UHFFFAOYSA-N niobium tantalum Chemical compound [Nb].[Ta] RHDUVDHGVHBHCL-UHFFFAOYSA-N 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 125000004433 nitrogen atom Chemical group N* 0.000 description 1
- 229910000069 nitrogen hydride Inorganic materials 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
- C22C29/02—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides
- C22C29/04—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbonitrides
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/90—Selection of catalytic material
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Ceramic Products (AREA)
- Cutting Tools, Boring Holders, And Turrets (AREA)
- Carbon And Carbon Compounds (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A sintered hard metal or cemented carbide is disclosed which consists of one or more hard materials consisting of molybdenum-tungsten-carbonitride having the structure of tungsten carbide in an amount of 50 to 99% by volume and a binder alloy of metals belonging to the iron group of the periodic system in amounts of 1 to 50 % by volume, characterized in that the contents of molybdenum and/or tungsten are at least partially substituted with one or more metals selected from the groups Cr, Nb, Ta, V or Re.
A sintered hard metal or cemented carbide is disclosed which consists of one or more hard materials consisting of molybdenum-tungsten-carbonitride having the structure of tungsten carbide in an amount of 50 to 99% by volume and a binder alloy of metals belonging to the iron group of the periodic system in amounts of 1 to 50 % by volume, characterized in that the contents of molybdenum and/or tungsten are at least partially substituted with one or more metals selected from the groups Cr, Nb, Ta, V or Re.
Description
3,~3~;8 CEMENTED CARBIDE
-Canadian patent Appln. 295,749 filed Jan. 26/78 relates to cemented carblde and hard materials or prlnclpals and to methods Or preparlng such mat;erials. Generally, the cemented carbides consist o~ one or more har-d materlal.s or hard principles in an amount of 50 to 99 %
by volume and a blnder metal or blnder metal. alloy ba~ed upon one or more Or the iron group metals ln an amount Or 1 to 50 ~ by volume.
In the cemented carbide the hard materials consist normally to the greatest part o~ tungsten carbide, WC, havlng a speclal hexagonal crystal structure, besides small amounts o~ carbides with sub-stantlally cubic crystal structure as ror example titanium-, tantalum-niobium-, harnium-, and vanadium carbide.
Tungsten carbide has many propertie~ making it speclally sulted as a hard material in cemented carbide. It has for example a great hot hardne~ and a high strength. Furthermore, the wettabillty between WC and binder metals as Co is excellent. Theae properties are particularly related to the mentloned hexagonal structure.
Many attempts have been made to substltute the relatlvely expenslve tungsten carbide by other hard materials but thls has either ~alled or has given rlse to products with changed or impalred properties.
One ha~ also attempted to substitute the W ln the tungsten carbide, partly or completely, wlth the related metal Mo. In most cases, however, thi~ has demanded speclal procedures, whlch have turned out to be completely uneconomical, or has given rise to hard materlal8 wlth unsatisfactory stabillty, partlcularly at high temperatures.
AB described in the patent application No. 295.,749 lt has been round, however, that a molybdenum-tungsten-carbonitrlde (Mo,W~(C,N~, havlng the same type or structure as WC and a better thermal stability than the correspondlng molybdenum-tungsten-carblde (Mo,W)C, can be obtalned by means of relatively ~lmple and economical method~ of manuractory. The mentioned carbonltride ha~ normally a nltrogen content Or 0.05-0.5 % by weight, but can have nltrogen ,.
113~8~8 contents of up to about 1.2-1.5% by weight at high contents of molybdenum.
Now, it has also been found that the hexagonal Mo-W-carbonitride which is unstable in certain respects can be further stabilized S by substituting Mo and/or W, partly or completely, with other metals as Cr, Nb, Ta, V and/or Re. The atomic radius of these elements is of such size that the carbonitride lattice shall not be distorted too much. Thus, by means of the invention further alternatives have been revealed to substitute the expensive and in certain cases rare tungsten raw materials. These alternatives also mean that still cheaper or more prevalent raw materials can be used than the molybdenum containing materials treated in the patent application 295,749.
In accordance with the present teachings, a cemented hard metal is provided comprising one or more hard materials in an amount of 70 to 97 percent by weight and a binder alloy of iron group metals in amounts of 3 to 30 percent by weight, the hard mater-ials consisting of at least 20 percent by weight of a molybdenum-tungsten-carbonitride which has the structure of tungsten car-bide WC with the molybdenum and/or tu~gsten being at least pa~ti-ally substituted for by a metal selected from the group consist-ing of Cr, Nb, Ta, V, Re and mixtures thereof.
In accordance with a further embodiment of the present teachings, an improvement is provided in the method of making a molybdenum-tungsten-carbonitride which has the structure of tungsten carbide WC wherein molybdenum, tungsten and carbon in proportions suffic-ient for formation of a monocarbide, are heated in a nitrogen-containing atmosphere at a temperature sufficient to form the molybdenum-tungsten-carbonitride. The improvement which is provided comprises substituting at least one metal M selected from the group consisti~-g of Cr, Nb, Ta, V, Re and mixtures thereof at least partly for the molybdenum and/or tungsten so as to form a carbonitride having the composition (MxMoyWz) (C,N) in which x = ~0 and up to 0.3 2a y = 0.0-0.95 z = 0.05-0.95 ancl x+y+z=l.
It has been found that the addition of chromium or of the other metals being equivalent in this respect will cause an increased solution of nitrogen at the sacrifice of carbon.
If the new carbonitride is written:
(CrxMoyWz) (C,N), in which x = 0-0.3 Y = 0-0 95 z = 0.05-0.95 and x + y + z = 1 (the metal Cr exemplifying the earlier mentioned group of metals) nitrogen contents between about 0.05 and about 15 atomic-% can be reached. This corresponds to nitrogen contents of up to about 3%
by weight in the carbonitride, which can be obtained at essential contents of Cr (or other nitride formers). Preferably, however, the carbonitride contains between about 0.05 and about 8.0 atomic -% nitrogen, which corresponds to a nitrogen content of up to about 2~ by weight.
The new carbonitride can be used in sintered cemented carbide in the same ways as what has been mentioned in the patent application 295,749 and it can be prepared according to earlier mentioned methods which, however, have to be somewhat modified with regard to the additional alloying elements.
.
3 ~34~368 mong other method~, molybdemlm-chromlum-tung~ten-carbonltride with hexagonal WC-structure can be prepared by heatlng Mo,W and Cr, possibly in bound rorm, together with C ln a ratio ~urficient ~or ~ormatlon o~ the mono-carbides, in a nitrogen containing atmosphere, preferably at temperatures between 1000 and 1500C. Above 1500C
al~o a pha~e ~ -M3 (C,N)2 i8 rormed, ln which M stands for Cr, Mo and/or W. Below 1000C the reaction proceed~ too slowly to be able to be used economically, In the manufacture al~o co-precipitated acids Or Mo and W, e.g.
H2(Mo,W)04 or mixtures of Mo- and W-aclds can be u~ed as starting materials. Also co-precipitated compounds Or molybdenum containing ammonium-para-tungstate are suitable. These can be prepared by neutrallzlng or evaporation of an ammoniacal ~olution of each oxide respectlvely.
It has been found that an addition of a chromium æalt facilitates the precipitation because a very fine-grained chromlum hydroxid 18 precipitated, actlng as nucleatlon ~ormer~ ~or the Mo- and W-compound~. In thi~ way, besides Mo-W- compounds, also Cr-contalning Mo-W- compounds can be prepared. It has also been round that the metal atoms Mo, W and Cr have to be mlxed very lntlmately, orten down to atomic level ln order to make the hexagonal carbonltrlde to rorm. Under these clrcumstances the reactlon to (Cr,Mo,W)(C,N) can be completed even if Cr~C2 and/or Mo2C,as an example, to~ether with WC do not normally form a solld solutlon when these components are thermally treated together.
The rormed carbonitride will usually be very flne-grained, but by means Or an additlon o~ some hundreths % by welght Or an alcall metal, e.g. Na, to the startlng materlals (berore the ~ormatlon Or oxide) the grain size of the hard materlal can be controlled.
In the rollowing example~ the preparation and properties Or the cemented carbide according to the inventlon wlll be additlonally illustrated, .
4 11'3~368 ~xample 1 -To a mlxture Or Mo 0~ and W03 disqolved ln ammonia, the atomlc ratlo Mo~W belng 1:1, there wa~ added chromium nltrate ln ~uch amounts that the atomlc ratlo Cr/Mo~W was 10/45/45, arter whlch the solution was evaporated to about 95 ~. The precipitate wa~
heated in air at 480C to a mixed oxlde Or the metals Cr, Mo and W. This oxlde was reduced with hydrogen at 950C rOr 2 h, rorming a metal powder whlch was slngle-phased and havlng the ~ame structure a~ W accordlng to X-ray di~ractlon measurements.
The metal powder was mlxed wlth carbon and heated in an atmo~phere Or 25~ by volume H2 ~nd 75 ~ by volume N2 at 1300C ~or 4 h. The amount of carbon was somewhat hyper-stoichlometrlc (about 1,05-1.10 tlme~ the stolchlometric amount) ln order to guarantee at least stolchiometrlc carbon content ln all parts o~ the sample. There was obtalned a product havlng 8.18 ~ by weight o~ bound carbon, 0.08 % by welght Or ~ree carbon, 0.27 ~ by weight Or nltrogen, 30.2 % by weight o~ Mo, 3.6 % by welght Or Cr and 57.7 ~ by weight Or W. By X-ray investigatlons it wa~ round khat the product oon-si~ted of a slngle-phase carbonltrlde havlng the ~ame type Or structure as WC and correspondlng to the rormula ~CrO loMOo 45Wo 45 (C,N~.
The carbonitrlde was mllled together wlth 12 % by welght o~ Co and 1.5 % by welght Or pre~slng agent ln a 2.4 llters ball mill ~or 48 hours. Arter presslng and slntering, 900C ln H2 and 1400C
ln vacuum, there were obtalned dense teBt ~peclmenB Or cemented carblde havlng the hardness, HV ~ = 1500, bending Btrength 1360 ~/mm2 and denslty 11.1 g/cm~.
Example 2 To an aqueous ammonla solutlon obtalned by dls~olvlng Mo 03 and W03 ln NH3, wlth the atomlc ratlo Mo~W belng 1:1, ohromlum was added as chromlumnitrate dissolved in nltrlc acld. By acldlrlcatlon wlth nltric acld to a pH o~ 1.2 at 90C a rlne-grained chromlum ¢ontalnlng molybdenum-tungsten acld was perclpltated ~lth the atomlc ratlo Or Cr/Mo~W belng 5/48/47. Arter cleanlng, dryinB t¢.
' ``
5 113~8f~3 ~e preclpitate was calcined at 480C for 2 h to a mixed oxlde o~
Cr, Mo and W. Thi~ oxlde waB reduced with hydrogen at 910C for 3 h to a single-pha~ed metal powder wlth the same structure ag tungsten according to X-ray difrractlon analy~es.
The mater~al was subsequently blended wlth carbon black and heated ln rlowlllg ammonla gas in a carbon tube ~urnace at 1000C ~or 5 h rollowed by a temperature ralse to 1450C whlch was malntained rOr
-Canadian patent Appln. 295,749 filed Jan. 26/78 relates to cemented carblde and hard materials or prlnclpals and to methods Or preparlng such mat;erials. Generally, the cemented carbides consist o~ one or more har-d materlal.s or hard principles in an amount of 50 to 99 %
by volume and a blnder metal or blnder metal. alloy ba~ed upon one or more Or the iron group metals ln an amount Or 1 to 50 ~ by volume.
In the cemented carbide the hard materials consist normally to the greatest part o~ tungsten carbide, WC, havlng a speclal hexagonal crystal structure, besides small amounts o~ carbides with sub-stantlally cubic crystal structure as ror example titanium-, tantalum-niobium-, harnium-, and vanadium carbide.
Tungsten carbide has many propertie~ making it speclally sulted as a hard material in cemented carbide. It has for example a great hot hardne~ and a high strength. Furthermore, the wettabillty between WC and binder metals as Co is excellent. Theae properties are particularly related to the mentloned hexagonal structure.
Many attempts have been made to substltute the relatlvely expenslve tungsten carbide by other hard materials but thls has either ~alled or has given rlse to products with changed or impalred properties.
One ha~ also attempted to substitute the W ln the tungsten carbide, partly or completely, wlth the related metal Mo. In most cases, however, thi~ has demanded speclal procedures, whlch have turned out to be completely uneconomical, or has given rise to hard materlal8 wlth unsatisfactory stabillty, partlcularly at high temperatures.
AB described in the patent application No. 295.,749 lt has been round, however, that a molybdenum-tungsten-carbonitrlde (Mo,W~(C,N~, havlng the same type or structure as WC and a better thermal stability than the correspondlng molybdenum-tungsten-carblde (Mo,W)C, can be obtalned by means of relatively ~lmple and economical method~ of manuractory. The mentioned carbonltride ha~ normally a nltrogen content Or 0.05-0.5 % by weight, but can have nltrogen ,.
113~8~8 contents of up to about 1.2-1.5% by weight at high contents of molybdenum.
Now, it has also been found that the hexagonal Mo-W-carbonitride which is unstable in certain respects can be further stabilized S by substituting Mo and/or W, partly or completely, with other metals as Cr, Nb, Ta, V and/or Re. The atomic radius of these elements is of such size that the carbonitride lattice shall not be distorted too much. Thus, by means of the invention further alternatives have been revealed to substitute the expensive and in certain cases rare tungsten raw materials. These alternatives also mean that still cheaper or more prevalent raw materials can be used than the molybdenum containing materials treated in the patent application 295,749.
In accordance with the present teachings, a cemented hard metal is provided comprising one or more hard materials in an amount of 70 to 97 percent by weight and a binder alloy of iron group metals in amounts of 3 to 30 percent by weight, the hard mater-ials consisting of at least 20 percent by weight of a molybdenum-tungsten-carbonitride which has the structure of tungsten car-bide WC with the molybdenum and/or tu~gsten being at least pa~ti-ally substituted for by a metal selected from the group consist-ing of Cr, Nb, Ta, V, Re and mixtures thereof.
In accordance with a further embodiment of the present teachings, an improvement is provided in the method of making a molybdenum-tungsten-carbonitride which has the structure of tungsten carbide WC wherein molybdenum, tungsten and carbon in proportions suffic-ient for formation of a monocarbide, are heated in a nitrogen-containing atmosphere at a temperature sufficient to form the molybdenum-tungsten-carbonitride. The improvement which is provided comprises substituting at least one metal M selected from the group consisti~-g of Cr, Nb, Ta, V, Re and mixtures thereof at least partly for the molybdenum and/or tungsten so as to form a carbonitride having the composition (MxMoyWz) (C,N) in which x = ~0 and up to 0.3 2a y = 0.0-0.95 z = 0.05-0.95 ancl x+y+z=l.
It has been found that the addition of chromium or of the other metals being equivalent in this respect will cause an increased solution of nitrogen at the sacrifice of carbon.
If the new carbonitride is written:
(CrxMoyWz) (C,N), in which x = 0-0.3 Y = 0-0 95 z = 0.05-0.95 and x + y + z = 1 (the metal Cr exemplifying the earlier mentioned group of metals) nitrogen contents between about 0.05 and about 15 atomic-% can be reached. This corresponds to nitrogen contents of up to about 3%
by weight in the carbonitride, which can be obtained at essential contents of Cr (or other nitride formers). Preferably, however, the carbonitride contains between about 0.05 and about 8.0 atomic -% nitrogen, which corresponds to a nitrogen content of up to about 2~ by weight.
The new carbonitride can be used in sintered cemented carbide in the same ways as what has been mentioned in the patent application 295,749 and it can be prepared according to earlier mentioned methods which, however, have to be somewhat modified with regard to the additional alloying elements.
.
3 ~34~368 mong other method~, molybdemlm-chromlum-tung~ten-carbonltride with hexagonal WC-structure can be prepared by heatlng Mo,W and Cr, possibly in bound rorm, together with C ln a ratio ~urficient ~or ~ormatlon o~ the mono-carbides, in a nitrogen containing atmosphere, preferably at temperatures between 1000 and 1500C. Above 1500C
al~o a pha~e ~ -M3 (C,N)2 i8 rormed, ln which M stands for Cr, Mo and/or W. Below 1000C the reaction proceed~ too slowly to be able to be used economically, In the manufacture al~o co-precipitated acids Or Mo and W, e.g.
H2(Mo,W)04 or mixtures of Mo- and W-aclds can be u~ed as starting materials. Also co-precipitated compounds Or molybdenum containing ammonium-para-tungstate are suitable. These can be prepared by neutrallzlng or evaporation of an ammoniacal ~olution of each oxide respectlvely.
It has been found that an addition of a chromium æalt facilitates the precipitation because a very fine-grained chromlum hydroxid 18 precipitated, actlng as nucleatlon ~ormer~ ~or the Mo- and W-compound~. In thi~ way, besides Mo-W- compounds, also Cr-contalning Mo-W- compounds can be prepared. It has also been round that the metal atoms Mo, W and Cr have to be mlxed very lntlmately, orten down to atomic level ln order to make the hexagonal carbonltrlde to rorm. Under these clrcumstances the reactlon to (Cr,Mo,W)(C,N) can be completed even if Cr~C2 and/or Mo2C,as an example, to~ether with WC do not normally form a solld solutlon when these components are thermally treated together.
The rormed carbonitride will usually be very flne-grained, but by means Or an additlon o~ some hundreths % by welght Or an alcall metal, e.g. Na, to the startlng materlals (berore the ~ormatlon Or oxide) the grain size of the hard materlal can be controlled.
In the rollowing example~ the preparation and properties Or the cemented carbide according to the inventlon wlll be additlonally illustrated, .
4 11'3~368 ~xample 1 -To a mlxture Or Mo 0~ and W03 disqolved ln ammonia, the atomlc ratlo Mo~W belng 1:1, there wa~ added chromium nltrate ln ~uch amounts that the atomlc ratlo Cr/Mo~W was 10/45/45, arter whlch the solution was evaporated to about 95 ~. The precipitate wa~
heated in air at 480C to a mixed oxlde Or the metals Cr, Mo and W. This oxlde was reduced with hydrogen at 950C rOr 2 h, rorming a metal powder whlch was slngle-phased and havlng the ~ame structure a~ W accordlng to X-ray di~ractlon measurements.
The metal powder was mlxed wlth carbon and heated in an atmo~phere Or 25~ by volume H2 ~nd 75 ~ by volume N2 at 1300C ~or 4 h. The amount of carbon was somewhat hyper-stoichlometrlc (about 1,05-1.10 tlme~ the stolchlometric amount) ln order to guarantee at least stolchiometrlc carbon content ln all parts o~ the sample. There was obtalned a product havlng 8.18 ~ by weight o~ bound carbon, 0.08 % by welght Or ~ree carbon, 0.27 ~ by weight Or nltrogen, 30.2 % by weight o~ Mo, 3.6 % by welght Or Cr and 57.7 ~ by weight Or W. By X-ray investigatlons it wa~ round khat the product oon-si~ted of a slngle-phase carbonltrlde havlng the ~ame type Or structure as WC and correspondlng to the rormula ~CrO loMOo 45Wo 45 (C,N~.
The carbonitrlde was mllled together wlth 12 % by welght o~ Co and 1.5 % by welght Or pre~slng agent ln a 2.4 llters ball mill ~or 48 hours. Arter presslng and slntering, 900C ln H2 and 1400C
ln vacuum, there were obtalned dense teBt ~peclmenB Or cemented carblde havlng the hardness, HV ~ = 1500, bending Btrength 1360 ~/mm2 and denslty 11.1 g/cm~.
Example 2 To an aqueous ammonla solutlon obtalned by dls~olvlng Mo 03 and W03 ln NH3, wlth the atomlc ratlo Mo~W belng 1:1, ohromlum was added as chromlumnitrate dissolved in nltrlc acld. By acldlrlcatlon wlth nltric acld to a pH o~ 1.2 at 90C a rlne-grained chromlum ¢ontalnlng molybdenum-tungsten acld was perclpltated ~lth the atomlc ratlo Or Cr/Mo~W belng 5/48/47. Arter cleanlng, dryinB t¢.
' ``
5 113~8f~3 ~e preclpitate was calcined at 480C for 2 h to a mixed oxlde o~
Cr, Mo and W. Thi~ oxlde waB reduced with hydrogen at 910C for 3 h to a single-pha~ed metal powder wlth the same structure ag tungsten according to X-ray difrractlon analy~es.
The mater~al was subsequently blended wlth carbon black and heated ln rlowlllg ammonla gas in a carbon tube ~urnace at 1000C ~or 5 h rollowed by a temperature ralse to 1450C whlch was malntained rOr
2 h. The amount of carbon added was somewhat hyperstolchlometrlc in order to prevent po~slble decarburization. The product obtalned had 7.74 % by welght bound carbon, 0.12 % by welght rree carbon, 0.38 % by weight nitrogeh, ~1.3 % by welght Mo, 1.8 % by weight Cr and 58.7 ~ by weight W, By X-ray investigatlons it was round that the product conslsted Or a single-phased carbonitride having the same type Or structure as WC.
The compound correspond~ to the rormula (CrO 05 MoO 48 W0 47 (Co.96 No.04~
As disclosed in application 295,749 the very invention relates essentially to a hard materlal ln the cemented carbldej l.e. a carbonltrlde havlng a hexagonal structure Or the same type as WC.
Now, it has also been round that hexagona~ (CrxMoyWz)(C,N) can be used ln other connections than as hard materlal ln s~ntered cemented carblde.
Tungsten carblde has ln the last years been notlced as a catalyst materlal in i.a. ruel cells ~or combustlon of hydrogen 8as, as WC
has catalytlc propertles slmllar to those o~ platlna trer. R.B. Levy~
M. Boudart, Science 181, 547 (1973). It has now been ~ound that also hexagonal (CrxMoyWz~(C,N) has a catalyelng ln~luence slmllar to platlna on particularly oxldlzlng reactions wlth hydrogen, and that ln many cases the actlvity can be greater than that Or pure WC.
This can among other thlngs be ascrlbed to the improved posslbllltles to obtain an extremely rine-gralned product (C l à 2 /um~ ¢ompared to WC. The pre3ence Or Cr also lncreases the corro8ion resl~tance 6 1~348tj8 ompared to WC. In certaln cases or ~urroundings the actual carbo-nitride has proved to be superlor to Pt, ror example when hlgh hardness and great wear resistance are demanded, partlcularly at increased temperatures.
The rea30n why the carbonitride according to the inventlon can be used ln electrochemical oxidizlng proce~es may be ascribed to the great density o~ d-electrons at and immedlately below the Fermi level (Platina show~ a similar behaviour~, By balancing the share of Cr-, Mo- and W-atoms and the ~hare o~ C- and N-atoms, respectlvely, the electron den~ity at the Fermi-level can be a~rected. Thls wlll also have an influence upon the magnetlc propertie8 o~the crystal which in its turn will a~ect the catalysing errects. The exact mechanism regarding this ln~luence has not yet been clarl~led, however. An in~luence on the catalyslng e~fect has also been fo~nd by doping the carbonitrlde with other metal~, es~entially elements belonging to the groups 4B, 5B and 6B Or the perlodic By3tem~ and Re, In using the hexagonal (W,Mo,Cr)-carbonitride ln ~uel cells and similar it can serve partly as a complement, partly as a sub~tltute ~or Pt and will thus decrea~e the need ror the later element.
The compound correspond~ to the rormula (CrO 05 MoO 48 W0 47 (Co.96 No.04~
As disclosed in application 295,749 the very invention relates essentially to a hard materlal ln the cemented carbldej l.e. a carbonltrlde havlng a hexagonal structure Or the same type as WC.
Now, it has also been round that hexagona~ (CrxMoyWz)(C,N) can be used ln other connections than as hard materlal ln s~ntered cemented carblde.
Tungsten carblde has ln the last years been notlced as a catalyst materlal in i.a. ruel cells ~or combustlon of hydrogen 8as, as WC
has catalytlc propertles slmllar to those o~ platlna trer. R.B. Levy~
M. Boudart, Science 181, 547 (1973). It has now been ~ound that also hexagonal (CrxMoyWz~(C,N) has a catalyelng ln~luence slmllar to platlna on particularly oxldlzlng reactions wlth hydrogen, and that ln many cases the actlvity can be greater than that Or pure WC.
This can among other thlngs be ascrlbed to the improved posslbllltles to obtain an extremely rine-gralned product (C l à 2 /um~ ¢ompared to WC. The pre3ence Or Cr also lncreases the corro8ion resl~tance 6 1~348tj8 ompared to WC. In certaln cases or ~urroundings the actual carbo-nitride has proved to be superlor to Pt, ror example when hlgh hardness and great wear resistance are demanded, partlcularly at increased temperatures.
The rea30n why the carbonitride according to the inventlon can be used ln electrochemical oxidizlng proce~es may be ascribed to the great density o~ d-electrons at and immedlately below the Fermi level (Platina show~ a similar behaviour~, By balancing the share of Cr-, Mo- and W-atoms and the ~hare o~ C- and N-atoms, respectlvely, the electron den~ity at the Fermi-level can be a~rected. Thls wlll also have an influence upon the magnetlc propertie8 o~the crystal which in its turn will a~ect the catalysing errects. The exact mechanism regarding this ln~luence has not yet been clarl~led, however. An in~luence on the catalyslng e~fect has also been fo~nd by doping the carbonitrlde with other metal~, es~entially elements belonging to the groups 4B, 5B and 6B Or the perlodic By3tem~ and Re, In using the hexagonal (W,Mo,Cr)-carbonitride ln ~uel cells and similar it can serve partly as a complement, partly as a sub~tltute ~or Pt and will thus decrea~e the need ror the later element.
Claims (9)
1. A cemented hard metal comprising one or more hard materials in an amount of 70 to 97 percent by weight and a binder alloy of iron group metals in amounts of 3 to 30 percent by weight, the hard materials consisting of at least 20 percent by weight of a molybdenum-tungsten-carbonitride having the structure of tungsten carbide WC with the molybdenum and/or tungsten being at least partly substituted for by a metal selected from the group consisting of Cr, Nb, Ta, V, Re and mixtures thereof.
2. The cemented hard metal of claim 1 wherein the carbonitride has a nitrogen content with the range of 0.05-15 atomic percent.
3. The cemented hard metal of claim 1 wherein the carbonitride has the composition (MxMoyWz) (C,N) wherein M is selected from the group consisting of Cr, Nb, Ta, V, Re and mixtures thereof and in which x = >0 and up to 0.3 y = 0.0-0.95 z = 0.05-0.95 and x + y + z = 1.
4. The cemented hard metal of claim 3 wherein M is Cr.
5. A carbonitride having the composition (MxMoyWz) (C,N) wherein M is selected from the group consisting of Cr, Nb, Ta, V, Re and mixtures thereof and in which x = >0 and up to 0.3 y = 0.0-0.95 z = 0.05-0.95 and x + y + z = 1.
6. The carbonitride of claim 5 wherein M is Cr.
7. The carbonitride of claim 5 wherein the nitrogen content is within the range of 0.05-15 atomic percent.
8. In a method of making a molybdenum-tungsten-carbonitride having the structure of tungsten carbide WC wherein molybdenum, tungsten, and carbon in proportions sufficient for formation of the monocarbide, are heated in a nitrogen-containing atmosphere at a temperature sufficient to form the said moly-bdenum-tungsten-carbonitride. the improvement comprising:
substituting at least one metal M selected from the group consisting of Cr, Nb, Ta, V, Re and mixtures thereof at least partly for the molybdenum and/or tungsten so as to form a carbonitride having the composition (MxMoyWz) (C,N) in which x = >0 and up to 0.3 y = 0.0-0.95 z = 0.05-0.95 and x + y + z = 1.
substituting at least one metal M selected from the group consisting of Cr, Nb, Ta, V, Re and mixtures thereof at least partly for the molybdenum and/or tungsten so as to form a carbonitride having the composition (MxMoyWz) (C,N) in which x = >0 and up to 0.3 y = 0.0-0.95 z = 0.05-0.95 and x + y + z = 1.
9. The method of claim 8 wherein said carbonitride formed at a temperature between 1000° and 1500°C.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE7802236-5 | 1978-02-28 | ||
| SE7802236A SE425003B (en) | 1978-02-28 | 1978-02-28 | MODIFICATION OF MOLYBDEN-VOLFRAM CARBONITRIDE ACCORDING TO THE REQUIREMENT OF PATENT 7800756-4 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1134868A true CA1134868A (en) | 1982-11-02 |
Family
ID=20334121
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000308054A Expired CA1134868A (en) | 1978-02-28 | 1978-07-25 | Cemented carbide |
Country Status (10)
| Country | Link |
|---|---|
| US (1) | US4300952A (en) |
| JP (1) | JPS54118314A (en) |
| AT (1) | AT366719B (en) |
| BR (1) | BR7804822A (en) |
| CA (1) | CA1134868A (en) |
| DE (1) | DE2829753A1 (en) |
| FR (1) | FR2418209A2 (en) |
| GB (1) | GB2015572B (en) |
| IT (1) | IT1112283B (en) |
| SE (1) | SE425003B (en) |
Families Citing this family (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0053018B1 (en) * | 1980-11-24 | 1984-09-05 | Exxon Research And Engineering Company | Novel molybdenum oxycarbonitride compositions |
| USRE34180E (en) * | 1981-03-27 | 1993-02-16 | Kennametal Inc. | Preferentially binder enriched cemented carbide bodies and method of manufacture |
| US4610931A (en) * | 1981-03-27 | 1986-09-09 | Kennametal Inc. | Preferentially binder enriched cemented carbide bodies and method of manufacture |
| FR2543152B1 (en) * | 1983-03-25 | 1985-06-14 | Eurotungstene Poudres | REFORMING CATALYSTS BASED ON TUNGSTENE AND / OR MOLYBDENE CARBIDES AND THEIR METHOD OF USE |
| SE440753B (en) * | 1983-05-13 | 1985-08-19 | Santrade Ltd | CUTTING PROCESSING TOOLS EXISTING CORE AND WRAP |
| SE453649B (en) * | 1984-11-09 | 1988-02-22 | Santrade Ltd | TOOLS IN THE FORM OF A COMPONENT BODY CONSISTING OF A CORE AND A HOLE |
| US4649084A (en) * | 1985-05-06 | 1987-03-10 | General Electric Company | Process for adhering an oxide coating on a cobalt-enriched zone, and articles made from said process |
| US4639352A (en) * | 1985-05-29 | 1987-01-27 | Sumitomo Electric Industries, Ltd. | Hard alloy containing molybdenum |
| SE462182B (en) * | 1986-09-01 | 1990-05-14 | Sandvik Ab | PROCEDURE FOR PREPARING A PROTECTIVE PLATE IN COMPOUND EXECUTIVE SUCH AS SPLIT PROTECTOR, COMPOUND ARM |
| US4857108A (en) * | 1986-11-20 | 1989-08-15 | Sandvik Ab | Cemented carbonitride alloy with improved plastic deformation resistance |
| JP2890592B2 (en) * | 1989-01-26 | 1999-05-17 | 住友電気工業株式会社 | Carbide alloy drill |
| ES2101741T3 (en) | 1989-12-28 | 1997-07-16 | Zapata Innovative Closures Inc | WRONG HANDLING COVERS AND METHODS TO MANUFACTURE THESE COVERS. |
| US5314656A (en) * | 1992-11-20 | 1994-05-24 | The Regents Of The University Of California | Synthesis of transition metal carbonitrides |
| IL110663A (en) * | 1994-08-15 | 1997-09-30 | Iscar Ltd | Tungsten-based cemented carbide powder mix and cemented carbide products made therefrom |
| US5580666A (en) * | 1995-01-20 | 1996-12-03 | The Dow Chemical Company | Cemented ceramic article made from ultrafine solid solution powders, method of making same, and the material thereof |
| JP3052240B2 (en) * | 1998-02-27 | 2000-06-12 | 東京タングステン株式会社 | Rotating anode for X-ray tube and method for producing the same |
| JP3347295B2 (en) * | 1998-09-09 | 2002-11-20 | 松下電器産業株式会社 | Component mounting tool and component mounting method and device using the same |
| EP1343736B1 (en) * | 2000-12-19 | 2009-03-04 | Honda Giken Kogyo Kabushiki Kaisha | Composite material |
| DE10297020T5 (en) * | 2001-07-03 | 2004-08-12 | Honda Giken Kogyo K.K. | Multi-component ceramic powder, method for producing multi-component ceramic powder, sintered body and method for producing a sintered body |
| JP2004142993A (en) * | 2002-10-24 | 2004-05-20 | Toshiba Tungaloy Co Ltd | Hexagonal composite carbide, and production method therefor |
| EP1420076A1 (en) * | 2002-10-24 | 2004-05-19 | Toshiba Tungaloy Co., Ltd. | Hard alloy and W-based composite carbide powder used as starting material |
| KR101434695B1 (en) * | 2006-09-14 | 2014-08-26 | 알베마를 네덜란드 비.브이. | Methods for recovering Group VI-B metals from waste catalysts |
| US8333923B2 (en) * | 2007-02-28 | 2012-12-18 | Caterpillar Inc. | High strength gray cast iron |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2036245A (en) * | 1932-01-11 | 1936-04-07 | Richard R Walter | Alloy |
| US3994692A (en) * | 1974-05-29 | 1976-11-30 | Erwin Rudy | Sintered carbonitride tool materials |
| US3971656A (en) * | 1973-06-18 | 1976-07-27 | Erwin Rudy | Spinodal carbonitride alloys for tool and wear applications |
| US4049876A (en) * | 1974-10-18 | 1977-09-20 | Sumitomo Electric Industries, Ltd. | Cemented carbonitride alloys |
| SE392482B (en) * | 1975-05-16 | 1977-03-28 | Sandvik Ab | ON POWDER METALLURGIC ROAD MANUFACTURED ALLOY CONSISTING OF 30-70 VOLUME PERCENT |
| US4049380A (en) * | 1975-05-29 | 1977-09-20 | Teledyne Industries, Inc. | Cemented carbides containing hexagonal molybdenum |
| US4120719A (en) * | 1976-12-06 | 1978-10-17 | Sumitomo Electric Industries, Ltd. | Cemented carbonitride alloys containing tantalum |
| US4101318A (en) * | 1976-12-10 | 1978-07-18 | Erwin Rudy | Cemented carbide-steel composites for earthmoving and mining applications |
| AT362943B (en) * | 1977-01-27 | 1981-06-25 | Sandvik Ab | Sintered hard metal |
| US4150984A (en) * | 1977-09-15 | 1979-04-24 | Ngk Spark Plug Co., Ltd. | Tungsten carbide-base sintered alloys and method for production thereof |
-
1978
- 1978-02-28 SE SE7802236A patent/SE425003B/en not_active IP Right Cessation
- 1978-07-06 DE DE19782829753 patent/DE2829753A1/en not_active Withdrawn
- 1978-07-18 AT AT0520478A patent/AT366719B/en not_active IP Right Cessation
- 1978-07-19 IT IT25892/78A patent/IT1112283B/en active
- 1978-07-20 GB GB7830472A patent/GB2015572B/en not_active Expired
- 1978-07-24 JP JP9089178A patent/JPS54118314A/en active Pending
- 1978-07-24 FR FR7821808A patent/FR2418209A2/en active Granted
- 1978-07-25 CA CA000308054A patent/CA1134868A/en not_active Expired
- 1978-07-26 BR BR7804822A patent/BR7804822A/en unknown
-
1979
- 1979-02-28 US US06/015,889 patent/US4300952A/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| IT1112283B (en) | 1986-01-13 |
| SE425003B (en) | 1982-08-23 |
| GB2015572A (en) | 1979-09-12 |
| FR2418209A2 (en) | 1979-09-21 |
| US4300952A (en) | 1981-11-17 |
| AT366719B (en) | 1982-05-10 |
| IT7825892A0 (en) | 1978-07-19 |
| GB2015572B (en) | 1982-09-22 |
| BR7804822A (en) | 1979-09-25 |
| DE2829753A1 (en) | 1979-08-30 |
| FR2418209B2 (en) | 1983-02-11 |
| JPS54118314A (en) | 1979-09-13 |
| ATA520478A (en) | 1981-09-15 |
| SE7802236L (en) | 1979-08-29 |
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