摘要
通过对聚晶金刚石在空气中差热(DTA)和热重(TG)曲线的分析,了解了其在空气中的氧化方式。继而利用扫描电镜对高频感应加热的复合片表面进行了观察,以了解其热损伤层的表面形貌和损伤深度。并据此确立了热损伤层深度与加热温度的对应关系。结果表明:(1)PCD受热时,主要是金刚石和金属钴与空气中的氧气发生放热反应,同时伴随着质量的损失;随着温度的升高,金刚石和金属钴的量都减少;(2)加热后PCD热损伤层是由钴氧化物的球状凸起,以及钴氧化物脱落后形成的微孔洞构成的;(3)热损伤层的深度与温度不成正比,在850℃左右有一最大值;对应于加热温度720℃、840℃、890℃,热损伤层的深度分别约为7μm、10μm和5μm。热损伤层的定量分析结果可以为热损伤层的去除提供理论指导。
Oxidation mode of polycrystalline diamond compact (PCD) in air was studied by analyzing the curves of DTA and TG differential thermal analysis and thermal gravimetric analysis. Furthermore, utilizing SEM, the morphology of PCD samples heated by hight frequency induction heating was observed to study the morphology and the depth of thermal damage layer of PCD. Based on this, the relationship between the depth of thermal damage layer and the heating temperature was built up. The results show that: (1) when PCD is heated, diamond and cobalt react with oxygen in air as an exothermic reaction, companied by mass loss of diamond and cobalt. Both diamond and cobalt loss in mass with increasing of temperature; (2) the thermal damage layer of PCD after heated is made by the extrusions and microholes left by the pull-off of cobalt oxides; (3) the depth of thermal damage layer is not in direct proportion to temperature, and there is a maximum value at about 850℃ . Corresponding to the heating temperature 720℃, 840℃ and 890℃, the depth of damage layer are respectively about 7μm, 10μm and 5μm. The result of quantitative analysis for thermal damage layer of PCD can provide theoretical guide for wiping off the damage layer.
出处
《金刚石与磨料磨具工程》
CAS
2004年第1期58-61,共4页
Diamond & Abrasives Engineering
