Abstract: To provide a raw material for high oxygen chromium targets containing oxygen in a form capable of effectively preventing the dust ejection phenomenon. A raw material for high oxygen chromium targets comprising chromium crystalline particles dispersed in metallic chromium wherein at least a portion of the surface of all the crystals constituting the oxide crystalline particles is in contact with the matrix of the metallic chromium. A method of producing a raw material for high oxygen chromium targets comprising chromium oxide crystalline particles dispersed in metallic chromium characterized by heat-treating metallic chromium containing a solid solution of oxygen or oxide particles as a starting material, and precipitating or crystal-growing the oxygen or oxide particles as chromium oxide crystalline particles having a particle size of 0.1 to 100 .mu.m, thereby obtaining a raw material for chromium targets.

Abstract: There is proposed a novel method for manufacturing high-purity metallic chromium that can eliminate the problems of reduced heating capability of the furnace, contamination of produced metallic chromium and other disadvantages related to the operation of the furnace. According to the invention, one or more than one of easily sulfidable metals selected from Sn, Ni and Cu are added to crude metallic chromium containing impurities and the mixture is loaded into a vacuum furnace equipped with heating elements of graphite and heated to 1,200.degree. to 1,500.degree. C. in an atmosphere with reduced pressure of between 0.1 and 5 torr.

Abstract: A raw material for high oxygen chromium targets comprising chromium crystalline particles dispersed in metallic chromium wherein at least a portion of the surface of all the crystals constituting the oxide crystalline particles is in contact with the matrix of said metallic chromium. And a method of producing a raw material for high oxygen chromium targets comprising chromium oxide crystalline particles dispersed in metallic chromium characterized by heat-treating metallic chromium containing a solid solution of oxygen or oxide particles as a starting material, and precipitating or crystal-growing the oxygen or oxide particles as chromium oxide crystalline particles having a particle size of 0.1 to 100, .mu.m, thereby obtaining a raw material for chromium targets.

Abstract: There is proposed a novel method for manufacturing high-purity metallic chromium that can eliminate the problems of reduced heating capability of the furnace, contamination of produced metallic chromium and other disadvantages related to the operation of the furnace. According to the invention, one or more than one of easily sulfidable metals selected from Sn, Ni and Cu are added to crude metallic chromium containing impurities and the mixture is loaded into a vacuum furnace equipped with heating elements of graphite and heated to 1,200.degree. to 1,500.degree. C. in an atmosphere with reduced pressure of between 0.1 and 5 torr.

Abstract: Chromium carbide powder and/or powder of an easily sulfidable metal are added to powdered crude metallic chromium to form a mixture thereof, which is then heated in vacuum to remove S, N and O by degassing so that consequently the crude metallic chromium is free from impurities to a possible maximum extent.Alternatively, powdered crude metallic chromium is heated in an atmosphere of inert gas to temperature between 800 and 1,400.degree. C. and then an easily sulfidable metal is added thereto to form a mixture thereof. Subsequently, the mixture is, directly or after adding carbon or chromium carbide, heated again in vacuum or in an atmosphere of inert gas to eliminate S, N and O by degassing so that the crude metallic chromium is free from impurities to a possible maximum extent.Still alternatively, powdered crude metallic chromium is washed with inorganic acid such as hydrochloric acid, sulfuric acid or nitric acid or organic acid such as acetic acid to remove metal impurities such as Fe.

Abstract: A thermite process for producing a pure metal or alloy by charging a reactor furnace with a mixture primarily containing a powdered metallic oxide and a reducing agent such as powdered aluminum, wherein a batch of the mixture of the starting materials is divided into a plurality of loading lots. The amount of heat generated by each of the loading lots of the starting materials is so regulated that the amount of heat generated by each loading lot differs from the amount of heat generated by other loading lots and the loading lots are sequentially arranged. The lots are loaded into a furnace to form layers for thermite reaction in an ascending order of heat generation.

Abstract: High-purity metallic chromium is produced by a method of initially preparing a mixture of chromium oxide, aluminum, carbon and an easily sulfidable metallic powder, and subsequently providing a thermite-reaction with the mixture to produce thermite-crude metallic chromium and a solid solution of carbon and easily sulfidable metal. Residual impurities in the thermite-crude metallic chromium are subsequently removed by heat treating the crude metallic chromium. This method produces high-purity metallic chromium advantageous for preparing corrosion and heat resistant chromium-containing alloys.