Diamond composite material and heat radiating member

A diamond composite material comprising:

• a diamond particle;
• carbide layer covering a surface of the diamond particle and consisting essentially of TiC;
• and
• binding material consisting of silver binding the diamond particle covered by the carbide layer together;
• wherein the diamond composite material has an oxygen content of 0.1 mass % or less;
• wherein the diamond particle in the diamond composite material has a surface at which, except for silver, only the carbide layer is present;
• wherein the diamond composite material has a cold and hot cycle endurance of 95% or more at −60° C. to 250° C. and has a thermal conductivity degradation rate less than 5% after being heated to 800° C.;
• wherein the TiC is made from TiH2;
• and
• wherein the TiC is made by a method comprising:
• preparing a mixture powder including the diamond particle and TiH2 in a container;
• depositing silver on the mixture powder to form a stack of layers in the container;
• increasing a temperature of the container to about 200° C. to 300° C., wherein the silver discharges oxygen and oxygen is contained in the layer of the mixture powder;
• further increasing the temperature to about 500° C. to 600° C., wherein TiH2 is chemically decomposed into Ti, hydrogen, and oxygen, and wherein hydrogen forms water vapor and is discharged from the mixture powder;
• and
• further increasing the temperature, wherein the silver enters into the mixture powder, takes in Ti, and Ti contacts the diamond particle to form the TiC.