Composite metal material and method for producing the same

A method for producing a composite metal material comprising:

• a step of preparing a solution containing a surfactant having both hydrophilicity and hydrophobicity;
• a step of dispersing a nanosized to micro-sized fine carbonaceous substance into a state of being monodispersed in said solution;
• a step of bringing said solution having said dispersed fine carbonaceous substance into contact with a surface of a metal powder particle;
• a step of drying said metal powder particle to make said fine carbonaceous substance in the monodispersed state adhere to the surface of said metal powder particle via a component of said solution;
• and
• a step of thermally decomposing and removing said solution component adhering to the surface of the metal powder particle by heat-treating said metal powder particle either in a hydrogen-containing reducing atmosphere or in a vacuum atmosphere to partially expose the surface of the metal powder particle out of the adhering fine carbonaceous substance, and thus progress diffusion and sintering among the metal powder particles through exposed parts.