Abstract: In a contact material, there is present in addition to silver, at least one higher melting point metal, metal alloy or metal compound. According to the invention, the material contains in addition to silver (Ag), at least iron (Fe) and/or titanium (Ti) in percent by weight of from 2 to 50%. Optionally, nitrides, carbides and/or borides of the metals titanium, zirconium and/or tantalum may also e present. It has been found that in their contact property spectrum such materials are largely equivalent to the material AgNi10. Thus the latter contact material can be replaced completely.

Abstract: The invention relates to a hard-metal body whose hard-metal phase consist of tungsten carbide and whose binder metal phase consists of nickel and chrome.Especially for the enhancement of the corrosion resistance it is proposed that the hard metal contain also TiN in addition to the hard-metal phase, whereby the content of TiN and and binder metal phase amounts to 5 to 25% by mass and is composed by 0.1 to 10% by mass TiN, 5 to 15% by mass chrome, the balance being made up by nickel.

Abstract: A dimensionally stable combustion synthesis product of a composition containing at least 20% by weight of a particulate combustible material; at least 15% by weight of a particulate filler material capable of providing desired mechanical and electrical properties; and up to 35% by weight of a particulate inorganic binder having a melting point lower than the combustion synthesis temperature. Electrodes suitable for electrochemical processing are a preferred product form, particularly electrodes for use in the electrowinning of aluminum from its oxide.

Abstract: A dispersion-strengthened (DS) alloy, more particularly oxide-dispersion-strengthened (ODS) iron-based alloys which manifest resistant to oxidation at temperatures as high as 1300.degree. C. (approx. 2400.degree. F.) whereby the alloys are useful in the production of advanced aircraft gas turbine engine components and in demanding industrial applications.

Abstract: A cermet alloy and a drill formed of the cermet alloy include hard dispersed phases and binder metal phases. The hard dispersed phases include a metal atom group containing titanium and a nonmetal atom group containing nitrogen. The amount of titanium contained in the metal atom group is at least 0.5 and not more than 0.95 as an atomic ratio. The amount of nitrogen contained in the nonmetal atom group is at least 0.1 and not more than 0.7 as an atomic ratio. The hard dispersed phases further include a fine grained portion having a mean grain size of at least 0.2 .mu.m and not more than 0.6 .mu.m and a coarse grained portion having a mean grain size of at least 1 .mu.m and not more than 3 .mu.m. The volume ratio of the fine grained portion to the course grained portion is at least 0.3 and not more than 3. The proportion of the binder metal phases contained in the cermet is at least 5 percent by weight and not more than 30 percent by weight.

Abstract: The invention relates to a composite hard metal body of hard material, a binder and embedded reinforcing material, as well as to a process for the production of the composite hard metal body by methods of powder metallurgy.In order to create a composite hard metal body with improved toughness under load, improved hardness and a lower fracture susceptibility, the invention proposes to build in monocrystalline, preferably needle-shaped and/or platelet-shaped reinforcing materials, coated with an inert layer with respect to the binder metal phase and consisting of borides and/or carbides, and/or nitrides and/or carbonitrides of the elements of Groups IVa or Va or mixtures thereof and/or coated monocrystalline reinforcing material of SiC, Si.sub.3 N.sub.4, Si.sub.2 N.sub.2 O, Al.sub.2 O.sub.3, ZrO.sub.2, AlN and/or BN.

Abstract: This invention relates generally to a novel method of preparing self-supporting bodies, and to novel products made thereby. In its more specific aspects, this invention relates to a method of producing self-supporting bodies comprising one or more boron-containing compounds, e.g., a boride or a boride and a carbide, by reactive infiltration of a molten parent metal actinide into (1) a bed or mass containing boron carbide and, optionally, (2) at least one of a boron donor material (i.e., a boron-containing material) and a carbon donor material (i.e., a carbon-containing material), (3) a bed or mass comprising a mixture of a boron donor material and a carbon donor material and, optionally, (4) one or more inert fillers in any of the above masses, to form the body.

Abstract: Neutron absorbing refractory B.sub.4 C--Gd and Gd.sub.2 O.sub.3 --Gd cermets, B.sub.4 C--Gd and Gd.sub.2 O.sub.3 --Gd metal-matrix composites, and B.sub.4 C--Gd.sub.2 O.sub.3 ceramic-ceramic composites can be manufactured by applying fundamental thermodynamic and kinetic guidelines as processing principals.Three steps are involved in the fabrication of these new compositions of matter. First, the starting materials are consolidated into a compacted porous green body. Next, the green body is densified using the appropriate method depending on the class of material sought: cermet, metal-matrix composite, or ceramic-ceramic composite. Finally, either during the densification process or by subsequent heat treatment, new phase evolution is obtained via interfacial chemical reactions occurring in the microstructures.The existence of a new phase has been identified in B.sub.4 C--Gd and B.sub.4 C--Gd.sub.2 O.sub.3 composites.

Abstract: A cermet alloy having a structure including a hard phase and a bonding phase which is composed of at least one ferrous metal, said bonding phase containing fine hard grains of a mean grain size not greater than 2000 .ANG. dispersed therein. The structure has a composition consisting of 10 to 70 wt % of TiCN, 5 to 30 wt % of WC, 5 to 30 wt % of NbC, 1 to 10 wt % of Mo.sub.2 C, 0.5 to 5 wt% of VC, 0.05 to 3 wt % of ZrC, 5 to 25 wt % of (Ni, Co), and not smaller than 2.5 wt% of total nitrogen and incidental impurities.

Abstract: A cermet alloy having a structure comprising a hard phase and a bonding phase, said hard phase comprising (1) at least one of MC, MN and MCN, wherein M is at least one element selected from Ti, Zr, Hf, Th, V, Nb, Ta, Pa, Cr, Mo, U and W and (2) at least one W-Co-B compound; said bonding phase comprising Co. The cermet has superior toughness and hardness, and can be worked by conventional sintering methods. The invention also includes a method for producing the cermet.

Abstract: Disclosed are a high toughness cermet comprising a sintered alloy comprising 75 to 95% by weight of a hard phase of carbide, nitride or carbonitride containing Ti, at least one of W, Mo and Cr, and N and C, and the balance of a binder phase composed mainly of an iron group metal, and inevitable impurities,wherein the content of Ti in said sintered alloy is 35 to 85% by weight calculated on TiN or TiN and TiC, and the contents of W, Mo and Cr are 10 to 40% by weight in total calculated on WC, Mo.sub.2 C and/or Cr.sub.3 C.sub.2,the relative concentration of said binder phase at the 0.01 mm-inner portion from the surface of said sintered alloy is 5 to 50% of the average binder phase concentration of the inner portion, and the relative concentration of said binder phase at the 0.1 mm-inner portion from the surface of said sintered alloy is 70 to 100% of the average binder phase concentration of the inner portion, anda compression stress of 30 kgf/mm.sup.

Abstract: Substantially dense, void-free ceramic-metal composites are prepared from components characterized by chemical incompatibility and non-wetting behavior. The composites have a final chemistry similar to the starting chemistry and microstructures characterized by ceamic grains similar in size to the starting powder and the presence of metal phase. A method for producing the composites requires forming a homogeneous mixture of ceramic-metal, heating the mixture to a temperature that approximates but is below the temperature at which the metal begins to flow and pressing the mixture at such pressure that compaction and densification of the mixture occurs and an induced temperature spike occurs that exceeds the flowing temperature of the metal such that the mixture is further compacted and densified. The temperature spike and duration thereof remains below that at which significant reaction between metal and ceramic occurs. The method requires pressures of 60-250 kpsi employed at a rate of 5-250 kpsi/second.

Abstract: A hard surfacing alloy which has a Rockwell C hardness of greater than about 50 and which includes tungsten carbide, chromium carbide and bi-metallic chromium and tungsten carbide crystals which are precipitated in the alloy. Alloys of the present invention in their nominal composition comprise from about 12% to about 20% tungsten; from about 13% to about 30% chromium; an effective amount of carbon for forming carbides with the tungsten and chromium and include effective amounts of fluxes and melting point depressants and the like. The balance of the composition is nickel. The alloys include precipitated carbide crystals of chromium, tungsten and bi-metallic mixtures thereof which are interspersed through the hard surfacing alloy and are metallurgically bonded in the metal matrix of the alloy. The alloys have extremely low porosities and therefore are suitable for glass plunger and other applications where low porosity is essential.

Abstract: According to the present invention there is now provided a method of making a sintered titanium-based carbonitride alloy. According to the method, melt-metallurgical raw materials containing the metallic alloying elements for hard constituent-forming as well as binder phase-forming elements are melted and cast, using no intentional additions of the elements C, N, B and O, to form a pre-alloy which in solidified condition of brittle intermetallic phases with hard constituent-forming and binder phase-forming elements mixed in atomic scale. The pre-alloy is crushed and/or milled to powder with grain size <50 .mu.m. The powder is carbonitrided for simultaneous formation in situ of extremely fine-grained <0.1 .mu.m, hard constituent particles enclosed in their binder phase.

Abstract: A magnetically anisotropic hot-worked magnet made of an R-T-B alloy containing a transition metal T as a main component, a rare earth element R including yttrium, and boron B; the magnet having the fine crystal grains having an average grain size of 0.02 -1.0 .mu.m, and having a carbon content of 0.8 weight % or less and an oxygen content of 0.5 weight % or less. The angular variance of orientation of the crystal grains is within 30.degree. from the C axes of the crystal grains when measured by X-ray. This magnet can be produced by mixing the magnet flakes with an additive composed of at least one organic compound having a boiling point of 50.degree. C. or higher.

Abstract: This invention relates to a process for producing a rare earth-containing material capable of being formed into a permanent magnet comprising crushing a rare earth-containing alloy and treating the alloy with a passivating gas at a temperature below the phase transformation temperature of the alloy. This invention further relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in a passivating gas at a temperature from ambient temperature to a temperature below the phase transformation temperature of the material. This invention also relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in water, drying the crushed alloy material at a temperature below the phase transformation temperature of the material, and treating the crushed alloy material with a passivating gas at a temperature from the ambient temperature to a temperature below the phase transformation temperature of the material.

Abstract: A hard, relatively non-brittle, cemented carbide body is made by sintering pressed grade carbide powders in the presence of a boron-containing material such as boron nitride. During sintering, appreciable quantities of boron migrate or diffuse into the body to become incorporated throughout the microstructure of the carbide resulting in the formation of a third quarternary phase comprised of tungsten, nickel, boron and carbon.

Abstract: A composite aluminum-base alloy having a mechanically alloyed matrix alloy. The matrix alloy has about 4-40 percent by volume aluminum-containing intermetallic phase. The aluminum-containing intermetallic phase includes at least one element selected from the group consisting of niobium, titanium and zirconium. The intermetallic phase is essentially insoluble in the matrix alloy below one half of the solidus temperature of the matrix alloy. The balance of the matrix alloy is principally aluminum. A stiffener of 5 to 30 percent by volume of the composite aluminum-base alloy is dispersed within the metal matrix.

Abstract: This invention relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in water, drying the crushed alloy material at a temperature below the phase transformation temperature of the material, and treating the crushed alloy material with a passivating gas at a temperature from the ambient temperature to a temperature below the phase transformation temperature of the material. Rare earth-containing alloys suitable for use in producing magnets utilizing the powder metallurgy technique, such as Nd-Fe-B and Sm-Co alloys, can be used. The passivating gas can be nitrogen, carbon dioxide or a combination of nitrogen and carbon dioxide. If nitrogen is used as the passivating gas, the resultant powder has a nitrogen surface concentration of from about 0.4 to about 26.8 atomic percent. Moreover, if carbon dioxide is used as the passivating gas, the resultant powder has a carbon surface concentration of from about 0.02 to about 15 atomic percent.

Abstract: A cutting insert of a sintered carbonitride alloy and with a complicated geometry, the insert having improved efficiency. This is obtained by giving the powder non-uniform compaction during pressing of the powder into a press-body so that the ultimate working edges will have a higher relative density than the surrounding, more "supporting" material in the press-body. By these means are often obtained surface defects in the form of cracks because of dissolved strains during the sintering.

Abstract: A sintered body for high-accuracy working tools is obtained by sintering powder mixture containing at least 45 percent by volume and not more than 60 percent by volume of cubic boron nitride powder having an average particle size of not more than 2 .mu.m and having a remainder formed of binder powder under a superhigh pressure. The binder contains at least 5 percent by weight and not more than 15 percent by weight of Al and at least 2 percent by weight and not more than 20 percent by weight of W, and has a binder remainder formed of a Ti compound or compounds. The atomic ratio of Ti contained in the binder to a transition metal element or elements belonging to any of the groups IVa, Va and/or VIa of the periodic table including Ti is at least 2/3 and not more than 97/100. In the structure of the sintered body, cubic boron nitride crystals are bonded with each other through bonding phases formed by the binder. When at least one or more Ti compounds are selected from a group of TiN.sub.z, Ti(C.sub.1-x N.sub.x).

Abstract: A dense cermet article including about 80-95% by volume of a granular hard phase and about 5-20% by volume of a metal phase. The granular hard phase consists essentially of a ceramic material selected from the hard refractory carbides, nitrides, carbonitrides, oxycarbides, oxynitrides, carboxynitrides, and borides of titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, boron, and mixtures thereof. The metal phase consists essentially of a combination of nickel and aluminum having a weight ratio of nickel to aluminum of from about 90:10 to about 70:30 and 0-5% by weight of an additive selected from the group consisting of titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, boron, or carbon, or combinations thereof. In the preferred metal phase, an amount of about 15-80% by volume of the metal phase component exhibits a Ni.sub.3 Al ordered crystal structure.

Abstract: Anisotropic permanent magnets consisting essentially of RE.sub.2 TM.sub.14 C are prepared by hot working suitable iron-neodymium/praseodymium-carbon containing alloys so as to produce deformed fine grains of the above essential magnetic phase.

Abstract: A dense cermet article including about 80-90% by volume of a granular hard phase and about 5-20% by volume of a metal phase. The hard phase is a carbide, nitride, carbonitride, oxycarbide, oxynitride, or carboxynitride of a cubic solid solution selected from W-Ti, W-Hf, W-Nb, W-Ta, Zr-Ti, Hf-Ti, Hf-Zr, V-Ti, Nb-Ti, Ta-Ti, or Mo-Ti. The metal phase consists essentially of a combination of nickel and aluminum having a ratio of nickel to aluminum of from about 90:10 to about 70:30 by weight, and 0-5% by weight of an additive selected from titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, boron, and/or carbon. The preferred hard phase is a cubic solid solution of tungsten and titanium. In the preferred metal phase, an amount of about 15-80% by volume of the metal phase component exhibits a Ni.sub.3 Al ordered crystal structure. The article may be produced by presintering the hard phase - metal phase component mixture in a vacuum or inert atmosphere at about 1475.

Abstract: A cermet contains 70 to 95 volume percentage of a hard dispersed phase and 30 to 5 volume percentage of a binder phase comprising one or more metals in group VIII (the iron group), wherein the hard dispersed phase contains as its components transitional metals in group IVb, transitional metals in group Vb, W alone of transitional metals in group VIb, C, and N, and consists of two structurally different types of particles. One type of the particles are single phase particles constituting 5% to 50% of the hard dispersed phase, whereas the other type of the particles are dual phase particles constituting 95% to 5% of the same. The cermet is for use in tools such as coating tools, spike pins, hobs, reamers, screw drivers, and so forth.

Abstract: A method for manufacturing a dense cermet article including about 80-95% by volume of a granular hard phase and about 5-20% by volume of a metal binder phase. The hard phase is (a) the hard refractory carbides, nitrides, carbonitrides, oxycarbides, oxynitrides, carboxynitrides, borides, and mixtures thereof of the elements selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and B, or (b) the hard refractory carbides, nitrides, carbonitrides, oxycarbides, oxynitrides, and carboxynitrides, and mixtures thereof of a cubic solid solution of Zr--Ti, Hf--Ti, Hf--Zr, V--Ti, Nb--Ti, Ta--Ti, Mo--Ti, W--Ti, W--Hf, W--Nb, or W--Ta. The binder phase is a combination of Ni and Al having a Ni:Al weight ratio of from about 85:15 to about 88:12, and 0-5% by weight of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Co, B, and/or C. The method involves presintering the hard phase/binder phase mixture in a vacuum or inert atmosphere at about 1475.degree.-1675.degree. C., then HIPing at about 1575.degree.-1675.degree. C.

Abstract: A method for the production of a metallic powder molding material is disclosed which comprises a step of imparting mechanical energy due to at least one of such physical actions as vibration, pulverization, attrition, rolling, shocks, agitation, and mixing a metallic particles in a vessel whose interior is held under vacuumized atmosphere or an atmosphere of inert gas thereby enabling the metallic particles to contact each other and acquire improvement in surface quality and a step of hot molding the metallic particles thereby producing a molding material.

Abstract: Reactive ceramic-metal compositions are described that include a ceramic phase of at least 70 percent by volume, 95 percent of theoretical density and a metal phase that retains its chemical reactivity with the ceramic phase after the composition has been fully densified. The composition may be heat treated after densification to form additional ceramic phases in a controllable manner. Preferred ceramic metal compositions wherein the metal and ceramic components retain reactivity after densification include boron carbide ceramic and Al or Mg metals. The process employed in forming said compositions requires first forming a sintered porous body of the ceramic material followed by contacting with the metal component, which may be in chip or solid bar form. The system is then heated to the melting point of the metal and a pressure of at least 200 MPa is employed such that the porous body is filled with metal and the composition is substantially fully densified.

Abstract: A high density metal-boride based ceramic sintered body consists essentially of component (A) at least one of TiB.sub.2, ZrB.sub.2, CrB.sub.2, HfB.sub.2, VB.sub.2, TaB.sub.2, NbB.sub.2, MnB.sub.2, MoB.sub.2, YB.sub.2, AlB.sub.2, MgB.sub.2, CrB, VB, TaB, NbB, MoB, HfB, YB, ZrB, HfB, TiB, MnB, W.sub.2 B.sub.5 and Mo.sub.2 B.sub.5, componet (B) 0.1 wt. %-10 wt. % based on the total amount of a metal binder comprising at least one of cobalt boride, nickel boride and iron boride, and component (C) 0.1 wt. %-10 wt. % based on the total amount of at least one of a double carbide comprising Ti, Zr, W and C, ZrCN, HfCN, or a double carbo-nitride comprising Ti, Zr, Hf and C, N.The sintered body is not easily oxidized and has extremely few pores and high shock resistance even using a fine grain raw material powder because component (C) has an oxygen removing effect during sintering.

Abstract: A hard sintered compact for tools is a sintered compact obtained by super-high pressure sintering of 45-75% by vol. of cubic boron nitride powder and the remaining proportion of binder powder. The binder includes 5-25% by wt. of Al and the remaining proportion of at least one species of compounds represented by (Hf.sub.1-z M.sub.z) C, where M denotes elements of IVa, Va and VIa groups in a periodic table except for Hf, and 0.ltoreq.z.ltoreq.0.3 is satisfied. Because of this composition, improvements are made in strength, wear resistance and heat resisting property of the binder, and a hard sintered compact for tools having excellent strength and excellent wear resistance can be obtained.

Abstract: Process for the powder-metallurgical production of work pieces, particularly tools, containing high-melting point carbides and/or carbonitrides homogeneously distributed in a matrix, in which an amount of elements of the IVa and Va groups, or secondary groups, of the periodic table is adjusted to at least 3 weight percent of the alloy, a low carbon and/or nitrogen concentration is established, and primary precipitates are prevented; and a desired carbon and/or nitrogen content is created by atomization of the melt into powder vaporizing medium.

Abstract: A method for fabricating a titanium aluminide composite structure consisting of a filamentary material selected from the group consisting of silicon carbide, silicon carbide-coated boron, boron carbide-coated boron, titanium boride-coated silicon carbide and silicon-coated silicon carbide, embedded in an alpha-2 titanium aluminide metal matrix, which comprises the steps of providing a first beta-stabilized Ti.sub.3 Al powder containing a desired quantity of beta stabilizer, providing a second beta-stabilized Ti.sub.3 Al powder containing a sacrificial quantity of beta stabilizer in excess of the desired quantity of beta stabilizer, coating the filamentary material with the second powder, fabricating a preform consisting of the thus-coated filamentary materials surrounded by the first powder, and applying heat and pressure to consolidate the preform.The composite structure fabricated using the method of this invention is characterized by its lack of a denuded zone and absence of fabrication cracking.

Abstract: A complex boride cermet having high strength and high toughness, which comprises a hard phase composed mainly of a boride of (Mo.sub.1-x W.sub.x).sub.2 NiB.sub.2 formed by substituting a part of Mo of Mo.sub.2 NiB.sub.2 by W, and a matrix alloy phase composed mainly of Ni and containing Mo, and a complex boride cermet comprising a hard phase composed mainly of Mo.sub.2 NiB.sub.2 or (Mo.sub.1-x W.sub.x).sub.2 NiB.sub.2 and a matrix of an alloy phase composed mainly of Ni and containing Mo, which is characterized in that carbon or/and nitrogen, and optionally at least one metal selected from the metals of Groups 4B and 5B and Cr, are incorporated to further improve the strength and toughness. Such complex boride cermet has high strength and high toughness and maintains such properties even at elevated temperatures of from 600.degree. to 900.degree. C.

Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal into a boron carbide material which may contain one or both of a boron donor material and a carbon donor material. The reactive infiltration typically results in a composite comprising a boron-containing compound, a carbon-containing compound and residual metal, if desired. The mass to be infiltrated may contain one or more inert fillers admixed with the boron carbide material, boron-containing compound and/or carbon-containing compound. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing varying volume percents of ceramic, metal, ratios of one ceramic to another and porosity.

Abstract: A nickel-based superalloy article formed from particles of the superalloy is processed to have a microstructure which is resistant to failure when processed using high strain thermomechanical processes. Articles having the desired microstrucuture are produced by hot isostatically pressing powder of the superalloy in a specified temperature range bounded by the incipient melting temperature as a minimum and the solvus temperature of stable high temperature phases. The compact is held under pressure in the specified temperature range to diffuse deleterious phases which exist as a result of the initial powder atomization operation. The powder compact thus formed can be processed using conventional processes to produce material for subsequent thermomechanical processing using high strain rate forging equipment and retain the benefits of chemical uniformity and cleanliness associated with traditional powder metal processes.

Abstract: An assembled cam shaft including a steel cam shaft member, a journal member made of sintered material and a cam lobe. The sintered material consisting essentially of 0.5 to 4.0% by weight of carbon, 0.1 to 0.8% by weight of phosphorus, 5 to 50% by weight of copper, 1% by weight or less of manganese, 2% by weight or less of silicon, and the balance being iron and impurities.

Abstract: A ternary metal matrix composite comprising a metallic binding matrix material and a reinforcement material consisting essentially of an insoluble ceramic and a semi-metal. The ternary metal matrix composite of the invention has a coefficient of thermal expansion which is lower and more consistent than that of known binary composites using similar materials. The coefficient of thermal expansion may be tailored to meet specific application needs. The invention also has a low density, good thermal conductivity, dimensional stability, and formability. In one form of the invention, the insoluble ceramic and semi-metal contain the same element. In a preferred form of the invention, the ternary metal matrix composite comprises an aluminum alloy matrix and a reinforcement material of silicon carbide and silicon.

Abstract: A dispersion strengthened copper alloy containing a copper matrix, and dispersion particles dispersed in the copper matrix within a range of 0.5 to 6 vol %. In this alloy, an average diameter of a matrix region where the dispersion particles are not present is 0.3 .mu.m or less, and the total amount of solid solution elements contained in the copper matrix is determined such that, when this amount of the solid solution elements is added to pure copper, the electric conductivity of the matrix is lowered by 5% IACS or less.

Abstract: A surface refined sintered alloy with a burnt surface, comprising 75 to 95% by weight of a hard phase containing Ti, C and N as the essential components and otherwise comprising at least one of Zr, Hf, V, Nb, Ta, Cr, Mo and W and the balance of the alloy comprising a binder phase composed mainly of Co and/or Ni and inevitable impurities, wherein the sintered alloy satisfies at least two conditions selected from the group consisting of the following (1) to (3):(1) the average grain size of the hard phase in a surface layer to the inner portion of 0.05 mm from the burnt surface of the sintered alloy is 0.8 to 1.2-fold of the average grain size of the hard phase in the inner portion of the sintered alloy excluding the surface layer;(2) the average content of the binder phase in the surface layer to the inner portion of 0.05 mm from the burnt surface of the sintered alloy is 0.7 to 1.

Abstract: There are disclosed a high strength nitrogen-containing cermet which comprises 7 to 20% by weight of a binder phase composed mainly of Co and/or Ni, with the balance being a hard phase composed mainly of TiC, TiN and/or Ti(C,N) and inevitable impurities, wherein the hard phase comprises 35 to 59% by weight of Ti, 9 to 29% by weight of W, 0.4 to 3.5% by weight of Mo, 4 to 24% by weight of at least one of Ta, Nb, V and Zr, 5.5 to 9.5% by weight of N and 4.5 to 12% by weight of C; and a process for preparing the same which comprises via the formulating, mixing, drying, molding and sintering steps of Co and/or Ni powder, at least one powder of TiC, Ti(C,N) and TiN, WC powder, Mo and/or Mo.sub.2 C, and at least one powder of carbides of Ta, Nb, V and Zr, wherein the sintering step is carried out by elevating the temperature up to 1350.degree. C. in vacuum, with the nitrogen atmosphere being made 1 torr at 1350.degree. C.

Abstract: Disclosed are a cermet alloy having excellent wear resistance and strength at elevated temperatures, and a composite mechanical part containing a strong layer of any such cermet alloy formed on the outer or inner surface of an alloy base.The materials which are used for making rolls, dies, punches, etc. are required to have excellent toughness, impact resistance, high-temperature strength and wear resistances. The conventional ultrahard WC--Co alloys are, however, unsatisfactory in high-temperature strength, through they have a satisfactorily high level of wear resistance. The conventional cermet alloys are low in toughness and impact strength, though they have high oxidation resistance. There has not been availabe any alloy that satisfies all of the requirements as herein-above stated.

Abstract: Disclosed is a process for obtaining a metallurgical bond between a metal material, or a composite material having a metal matrix, and a metal casting, or a metal alloy casting, which comprises carrying out a surface treatment on said material by means of the deposition of a thin layer of a metal, generally different from the metals contained in the material and in the casting, which is capable of increasing the wettability between the metal of the casting and the material, as well as the heat transfer coefficient between said two partners; and a step of casting around the same material, positioned inside a mold, of the metal, or of the metal alloy the same casting is constituted by.

Abstract: The invention relates to sintered hard metals having high cutting properties, particularly plastic deformation resistance at high temperatures, crater resistance and the like, suitable for use as cutting tools, wear resistant tools and materials for dies, and the method for producing the same. The invention has for an object to obtain both sintered hard metals having the aforesaid high properties by sintering metallic components comprising IVa group metals, VIa group metals or metals of both groups substituted by Va group metals up to 60 mol % respectively, a B-1 type solid solution hard phase consisting of non-metallic components of C, N and O, and a metallic bonding phase, in a CO gas atmosphere, and to sintered hard metals in which an uniform hardness is imparted to the surface and interior thereof by the method of sintering the said sintered hard metal in a CO gas atmosphere.

Abstract: Erosion and abrasion resistant refractory metal carbide articles are provided having multiphase alloy of borides including titanium boride, binder metal boride, and titanium-binder metal-refractory metal borides by diffusion of titanium initially to convert the refractory metal carbide to its constitutents which are then reacted with boron, forming a new added surface in replacement of the original article surface, and bridging the original surface locus.

Abstract: A sintered ferro alloy comprises 5 to 25 wt % of one or two elements selected from Mo and W, 2 to 10 wt % of Cr, 0.1 to 0.9 wt % of Si, less than or equal to 0.7 wt % of Mn, less than or equal to 0.05 wt % of P, 0.5 to 2.0 wt % of C, 0.5 to 2.0 wt % of B, 0.1 to 7.0 wt % of at least one element selected from borides of La, Ce, Nd, Sm, Eu, Gd, Yb, Y or Sc, residual Fe, and contaminants. Also the alloy may comprise less than or equal to 20 wt % of at least one element selected from V, Nb, Ta, Ti, Zr, Hf, Co or Ni, if necessary. The alloy is produced by mixing the above mentioned components and pressurizing them in an Fe matrix, then sintering the pressurized mixture at 1150.degree. C. to 1260.degree. C. for 60 min. and reheating after sintering. This alloy has wear and heat resistance and can be utilized as valve seats for internal combustion engines in automotive vehicles.

Abstract: Substantially dense, void-free ceramic-metal composites are prepared from components characterized by chemical incompatibility and non-wetting behavior. The composites have a final chemistry similar to the starting chemistry and microstructures characterized by ceramic grains similar in size to the starting powder and the presence of metal phase. A method for producing the composites requires forming a homogeneous mixture of ceramic-metal, heating the mixture to a temperature that approximates but is below the temperature at which the metal begins to flow and presssing the mixture at such pressure that compaction and densification of the mixture occurs and an induced temperature spike occurs that exceeds the flowing temperature of the metal such that the mixture is further compacted and densified. The temperature spike and duration thereof remains below that at which significant reaction between metal and ceramic occurs. The method requires pressure of 60-250 kpsi employed at a rate of 5-250 kpsi/second.

Abstract: A hard, relatively non-brittle, cemented carbide body is made by sintering pressed grade carbide powders in the presence of a boron-containing material such as boron nitride. During sintering, appreciable quantities of boron migrate or diffuse into the body to become incorporated throughout the microstructure of the carbide resulting in the formation of a third quarternary phase comprised of tungsten, cobalt, boron and carbon.

Abstract: This invention provides a cermet alloy improved in toughness high-temperature strength and chipping resistance. This cermet alloy consists essentially of 50-95% by weight of a hard phase of a composite carbo-nitride of at least both of W and Ti and, optionally, one or more elements selected from the group consisting of Groups 4a, 5a and 6a elements of the periodic table, the balance being a binding phase, of an Fe family element or elements and inevitable impurities, said composite carbo-nitride has a rim-and-core structure which comprises a core portion of a composite carbo-nitride poor in Ti and nitrogen, surrounded thereon by a rim portion of a composite carbo-nitride rich in Ti and nitrogen. It is preferred that the hard phase consists of 50% by volume or less of TiN or TiCN particles having N.gtoreq.C and forming no rim-and-core structure and the composite carbo-nitride having the rim-and-core structure.

Abstract: A metallizing composition essentially consists of given amounts of Ni, Nb, Cr, C, Si, Zr, SiC and W and is used for metallizing the surface of ceramics such as Si.sub.3 N.sub.4, SIALON, A1N, high purity alumina and so on. This composition forms a metallized layer having an excellent bonding strength to the ceramic surface.

Abstract: Cemented carbide substrates having substantially A or B type porosity and a binder enriched layer near its surface are described. A refractory oxide, nitride, boride, and/or carbide coating is deposited on the binder enriched surface of the substrate. Binder enrichment is achieved by incorporating Group IVB or VB transition elements. These elements can be added as the metal, the metal hydride, nitride or carbonitride.