纳米金刚石高压烧结实验研究

Research of nano-diamond high-pressure sintering

文章旨在研究采用平均粒度为50nm的金刚石微粉在不同合成压力,烧结温度和烧结时间工艺条件下所得的纳米PCD的微观结构和力学性能。在实验中采用的合成压力分别为6.12GPa、5.19GPa,烧结温度为1028℃、1180℃,烧结时间分别为110s、180s。分别采用了SEM、XRD对合成的纳米PCD样品的微观结构进行表征,并测试了磨耗比以表征其耐磨性。结果表明,仅在6.12GPa、1028℃、110s的合成工艺条件下纳米金刚石微粉烧结成团,且获得了3280的磨耗比;纳米金刚石表面的吸附基团是造成纳米金刚石烧结样品性能低的主要原因;烧结样品中石墨峰的存在,说明或由于烧结温度过高、压力过低,抑或是由于烧结时间太长造成了金刚石的石墨化。

This paper aims to study the microstructure and mechanical properties of nano- PCD under different pressure, sintering temperature and sintering time with the nano- diamond powder which average particle size is 50nm. Synthesis pressure used in the exper- iment is 6.12GPa, 5.19GPa, the sintering temperature is 1028℃, 1180℃, sintering time is 110s, 180s. The microstructure of nano-PCD was analyzed through SEM, XRD, and tested the abrasion ratio to characterize the wear resistance. The result show that only under the condition of 6.12GPa, 1028℃, 110s nano-diamond powder sintered into a group with a 3280 abrasion ratio; the adsorbate on the surface of nano-diamond powder is the main factor of poorer performance of the nano-PCD; appearing a little graphite peak indicates that the diamond having graphitized caused by too high temperature or too long sintering time.