在人造金刚石聚晶(或复合片)的合成过程中,对于“线度比”大的样品(薄片型或细长型)来说,容易发生破裂或断裂是一个普遍存在的问题。其主要原因有两个:一是因为冷却速度太快、而样品的导热率又不高、产生的热应力太大而导致破裂。另一个原因是在热压致密过程中,由于边界润滑不良而导致样品各部分致密程度不一致、也将引起样品容易破裂。 In the synthetic diamond polycrystalline (or composite) process, it is a common problem that a “sharpness ratio” large sample (sheet type or slender type) is likely to be cracked or broken. There are two main reasons: First, because the cooling rate is too fast, and the thermal conductivity of the sample is not high, resulting in thermal stress is too large and lead to rupture. Another reason is that in the process of hot pressing and densification, the density of each part of the sample is not consistent due to the poor lubrication on the boundary, which also causes the sample to be easily broken.