| 摘要 |
A sintered material and the tough-coated hard powder (TCHP) to make such a material is comprised of core particles that consist essentially of a first metal compound having the formula MaXb. M is a metal selected from the group consisting of titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, aluminum, boron and silicon while X represents one ormore elements selected from the group consisting of nitrogen, carbon, boron and oxygen. The letters a and b represent numbers greater than zero up to and including four. The core particles are surrounded by an intermediate layer consisting essentially of a second metal compound, different in composition from the first metal compound thereby forming coated particles. The material of the intermediate layer has a higher relative fracture toughness than the material comprising the core particles and is capable of bonding with the metal compound(s) forming the core particles and also being capable of bonding with iron, cobalt or nickel. The coated particles are surrounded by an outer layer of iron, cobalt, nickel, their alloys, their mixtures and their intermetallic compounds. The intimate liaison of multiproperty alloys within the TCHP grains allows the combination of normally conflicting sintered article performance characteristics (e.g., strength and hardness) at levels heretofore unseen in the powder metallurgical art. |
