【摘要】 聚晶金刚石(PCD)刀具在加工非铁基材料时,尤其是一些超硬、耐磨材料时,其寿命和加工精度远高于传统刀具。聚晶金刚石的性能与原材料和烧结条件密切相关。概述了不同因素对以陶瓷为粘结剂的聚晶金刚石和无粘结剂的纳米聚晶金刚石的硬度、断裂韧性的影响并比较了不同种类PCD的热稳定性能。分析得到以过渡金属硼化物和碳化硅为粘结剂所制备的PCD的热稳定性能较好,优于以钴为粘结剂制备的PCD;在Hall-Petch定律作用下,以纳米尺寸陶瓷为粘结剂的PCD硬度更高,韧性更强;无粘接剂的纳米聚晶金刚石的力学、热学性能最为优异。最后,结合实际应用对聚晶金刚石的制备提出了参考性的建议。更多还原

【Abstract】 The service life and machining accuracy of polycrystalline diamond(PCD)cutting tool are superior to traditional ones when used for machining non-iron based materials,superhard and wear-resistant materials.The performances of PCD are related to raw materials and sintering conditions.This paper summarizes the hardness,fracture toughness and thermal stability of PCD sintered with different binders or without binder which is nano-polycrystalline diamond(NPD).The results indicate PCD using transition metal borides or SiC as binders possesses better thermal stability compared to PCD using Co as binder.Due to Hall-Petch law,PCD sintered with nano-sized binder have higher hardness and stronger toughness in comparison with that sintered with micron-sized binder.NPD displays the best performance in hardness,fracture toughness and thermal stability.At last,we put forward some pertinence advice on the preparation of PCD materials based on practical application.更多还原