初始材料中Al含量对CBN复合片烧结行为的影响

Effect of Al content in the starting mixture on the sintering behavior of CBN-based compacts

探索了以Al作为烧结助剂,压力为5.0 GPa,烧结温度在1 400℃情况下,初始材料中Al的含量对CBN复合片中反应机理和机械性能的影响。通过对CBN基复合片的硬度、微观形貌以及物相的分析,发现CBN和Al的反应、以及CBN复合片的机械性能严重依赖于初始材料中A l的含量。除次之外,本文首次采用晶格常数精确计算来分析了化学反应中B原子去向。实验结果表明:当初始混合粉末中Al的含量不超过15%时,复合片的微观结构都比较均匀,硬度都超过30 GPa。含15%A l的样品具有最好的切削性能。

In this paper,the effect of Al content in the starting mixture on the reaction mechanism and mechanical performance of CBN-based compact sintered at 5.0 GPa and 1 400 ℃ was studied.Based on the hardness test,microstructure and phase composition analysis,it was found that the reaction between CBN and Al,as well as the mechanical performance of CBN-based compacts,strongly depended on the Al content of the starting mixtures.In addition,we calculated the lattice constants of AlN accurately to analyse the fate o...