| 摘要 |
PURPOSE:To improve toughness by sealing specific polycrystalline diamond powder of raw material for sintering in a metallic capsule, generating high pressure and high temperature under a specific condition and sintering. CONSTITUTION:Polycrystalline diamond powder 2 of raw material for sintering having 10-100nm diameter of primary particles, 100nm-1mum minimum diameter of secondary particles and 100nm-10mum maximum particle of secondary particles is packed into a metallic capsule 1, a cover 3 is screwed into the capsule, the capsule is evacuated through a hole 4 and the hole 4 is sealed. Then the capsule 1 is packed into a momentum trap consisting of a combination of a storage part 5 of test specimen, a ring 6 and a disc 7, embedded in clay 9, a plane wave generator 17 is placed through a steel plate 14 and an explosive compound 15 on the trap. Then the explosive compound 15 is exploded through a detonator 18, the shot metallic plate or bullet is collided at more than 1.8kg/second velocity when calculated as a collision condition between stainless steels SUS 304, high pressure and high temperature are generated, the diamond is sintered, the polycrystalline diamond powder is directly bonded to give sintered material of diamond having >=90% density free from orientation. |
