Aqueous Solution Composition and Method for Manufacturing the Same, Oxide Powder and Method for Manufacturing the Same, Carbide Powder and Method for Manufacturing the Same, and Cemented Carbide and Method for Manufacturing the Same

A cemented carbide comprising:

• solid solution particles having an average particle size of less than or equal to 50 nm;
• and
• a binder phase,
• the solid solution particles containing more than or equal to 0.1 mass % and less than or equal to 20 mass % of a transition metal, and a remainder of tungsten and carbon,
• the transition metal including cobalt,
• the transition metal further including at least one selected from the group consisting of vanadium, chromium, zirconium, niobium, tantalum, hafnium, and manganese,
• the binder phase containing cobalt which is not dissolved in the solid solution particles.

A method for manufacturing an aqueous solution composition, comprising:

• preparing a first aqueous solution by dissolving a tungsten oxide in ammonia water;
• preparing a second aqueous solution by dissolving an organic acid in the first aqueous solution;
• preparing a dry solid matter by drying the second aqueous solution at a temperature lower than a decomposition temperature of the organic acid;
• preparing a third aqueous solution by dissolving the dry solid matter in water;
• and
• manufacturing an aqueous solution composition by mixing an acid aqueous solution containing at least a cobalt salt into the third aqueous solution.

A method for manufacturing an oxide powder, comprising:

• preparing a first aqueous solution by dissolving a tungsten oxide in ammonia water;
• preparing a second aqueous solution by dissolving an organic acid in the first aqueous solution;
• preparing a dry solid matter by drying the second aqueous solution at a temperature lower than a decomposition temperature of the organic acid;
• preparing a third aqueous solution by dissolving the dry solid matter in water;
• manufacturing an aqueous solution composition by mixing an acid aqueous solution containing at least a cobalt salt into the third aqueous solution;
• and
• manufacturing an oxide powder by spray-drying the aqueous solution composition at a temperature of more than or equal to 500° C. and less than or equal to 1500° C. by a spray pyrolysis technique.

A method for manufacturing a carbide powder, comprising:

• preparing a first aqueous solution by dissolving a tungsten oxide in ammonia water;
• preparing a second aqueous solution by dissolving an organic acid in the first aqueous solution;
• preparing a dry solid matter by drying the second aqueous solution at a temperature lower than a decomposition temperature of the organic acid;
• preparing a third aqueous solution by dissolving the dry solid matter in water;
• manufacturing an aqueous solution composition by mixing an acid aqueous solution containing at least a cobalt salt into the third aqueous solution;
• manufacturing an oxide powder by spray-drying the aqueous solution composition at a temperature of more than or equal to 500° C. and less than or equal to 1500° C. by a spray pyrolysis technique;
• and
• manufacturing a carbide powder by heating the oxide powder in an inert atmosphere in co-presence of an organic nitrogen compound containing at least one of a cyano group and an amino group.

A method for manufacturing a cemented carbide, comprising:

• preparing a first aqueous solution by dissolving a tungsten oxide in ammonia water;
• preparing a second aqueous solution by dissolving an organic acid in the first aqueous solution;
• preparing a dry solid matter by drying the second aqueous solution at a temperature lower than a decomposition temperature of the organic acid;
• preparing a third aqueous solution by dissolving the dry solid matter in water;
• manufacturing an aqueous solution composition by mixing an acid aqueous solution containing at least a cobalt salt into the third aqueous solution;
• manufacturing an oxide powder by spray-drying the aqueous solution composition at a temperature of more than or equal to 500° C. and less than or equal to 1500° C. by a spray pyrolysis technique;
• manufacturing a carbide powder by heating the oxide powder in an inert atmosphere in co-presence of an organic nitrogen compound containing at least one of a cyano group and an amino group;
• and
• manufacturing a cemented carbide by sintering the carbide powder.