Abstract: A method is disclosed for preparing an intimate mixture of powders of nickel-boron-silicon alloy and molybdenum metal powder suitable for thermal spray coatings which comprises milling a starting mixture of the alloy and molybdenum powder to produce a milled mixture wherein the average particle size is less than about 10 micrometers in diameter, forming an aqueous slurry of the resulting milled mixture and a binder which can be an ammoniacal molybdate compound or polyvinyl alcohol, and agglomerating the milled mixture and binder. The intimate mixture and binder are preferably sintered in a reducing atmosphere at a temperature of about 800.degree. C. to about 950.degree. C. for a sufficient time to form a sintered partially alloyed mixture wherein the bulk density is greater than about 1.2 g/cc.

Abstract: A process is disclosed for producing chromium oxide powders, which comprises forming an aqueous slurry wherein the solids content is a mixture which consists essentially of in percent by weight about 5 to 15 chromium acetate and the balance chromium oxide, agglomerating the mixture, sintering the resulting agglomerated mixture in a hydrogen atmosphere at a temperature at about 1400.degree. C. to about 1550.degree. C. in metallic vessels, entraining the sintered chromium oxide powder in a carrier gas, passing the sintered chromium oxide powder and the carrier gas through a plasma flame at a power of about 10 to about 80 KW using an inert gas as the plasma gas, and cooling the resulting plasma heated chromium oxide powder to produce free flowing chromium oxide powder having a free chromium content of less than about 1% by weight.

Abstract: A method is disclosed for producing a Wc-Co-Cr alloy which comprises alloying a mixture consisting essentially of in percent by weight of from about 85 to about 90 tungsten carbide, wherein the particle size of the tungsten carbide is less than about 1 micrometer in diameter, from about 9 to about 11 cobalt metal powder, wherein the particle size of the cobalt is from about 1 to about 5 micrometers in diameter, and from about 3.5 to about 4.5 chromium wherein the chromium is provided as chromium carbide to produce a Wc-Co-Cr alloy the alloy capable of being used as a coating wherein the hardness of the coating is from about 1060 to about 1240 DPH carbide hardness and from about 870 to about 980 DPH matrix hardness and wherein the roughness is from about 190 to about 200 AA.

Abstract: A process is disclosed for producing plasma type spray powders. The process involves forming, an admixture of a base metal, chromium, aluminum, and yttrium or master alloy powders containing these elements, and dry milling the admixture by high shearing to produce a homogeneous mixture. A slurry of this mixture and an aqueous solution of a binder is then spray dried to produce agglomerates, the major portion of which has a particle size of from about 20 to about 53 microns. This major portion is then separated from the remainder of the agglomerates and sintered in a reducing atmosphere to remove the binder and form a sintered powder. The sintered powder is then passed through a high temperature plasma reactor to melt the powder and produce a homogeneous plasma spray powder.

Abstract: A process is disclosed for producing composite agglomerates of molybdenum and molybdenum carbide (Mo.sub.2 C). The process involves forming a relatively uniform mixture of non-agglomerated molybdenum powder and carbon powder having a particle size of no greater than the particle size of the molybdenum powder. The amount of carbon powder is proportional to the amount of molybdenum carbide desired in the composite agglomerate. A slurry is formed of the mixture, an organic binder, and water with the amount of the binder being no greater than about 2% by weight of the mixture; and the powders are agglomerated from the slurry. The agglomerated powders are then classified to remove the major portion of the agglomerates having a size greater than about 170 mesh and less than about 325 mesh from the balance of the agglomerates. The balance of the agglomerates in which the particle size is -170 +325 mesh is then reacted at a temperature of no greater than about 1400.degree. C.

Abstract: A process for forming a homogeneous mixture of yttrium oxide and zirconium oxide involves dissolving yttrium oxide and hydrochloric acid in water, precipitating yttrium hydroxide by adding ammonium hydroxide to the solution and dissolving yttrium hydroxide in acetic acid, adding zirconium oxide to the resulting solution which is thereafter spray dried to yield an agglomerate having uniformly distributed yttrium acetate throughout and thereafter converting the yttrium acetate to yttrium oxide to yield an agglomerate having uniform distribution of yttrium oxide and zirconium oxide. The yttrium oxide/zirconium oxide agglomerates have a particle size of from about 20 to about 200 microns. The intermediate agglomerate contains a uniform distribution of yttrium acetate and provides a composition which can be converted to a yttrium oxide/zirconium oxide agglomerate having a homogeneous mixture of the two components.

Abstract: A method is disclosed for introducing a controlled level of oxygen into agglomerated molybdenum metal powder, involving heating the powder at a sufficient temperature for a sufficient time in the presence of water vapor, and a non-oxidizing atmosphere with the amount of non-oxidizing atmosphere being controlled to produce a partially oxidized molybdenum powder.

Abstract: A method is disclosed for introducing a controlled level of oxygen into agglomerated molybdenum plasma spray powder. The method involves forming a relatively uniform mixture of agglomerated powders consisting essentially of molybdenum and one or more oxygen containing compounds of molybdenum wherein said mixture has an oxygen content of greater than about 10% by weight and reducing the mixture at a sufficient temperature for a sufficient time to remove a portion of the oxygen therefrom and form a molybdenum powder having an oxygen content of no greater than about about 10% by weight.

Abstract: A plasma spray powder having a substantially uniform composition consisting essentially of a metal selected from the group consisting of cobalt, nickel, iron, mixtures and alloys thereof the balance consisting essentially of tungsten and carbon in a ratio of about one mole of carbon per one mole of tungsten wherein the ratio of iron and nickel to cobalt is at least about 4 to one.

Abstract: A free flowing plasma spray powder of substantially spherical particles having substantially smooth surfaces and of uniform composition consisting essentially of about 4 to about 6 percent by weight rhenium with the balance being tungsten.