金属TiC陶瓷刀具断裂失效分析

Fracture Failure Analysis of TiC Ceramic Cutter

从金相组织及断口形貌两个方面对切割硬质材料的某金属陶瓷刀具断裂的原因进行了分析。结果表明,刀刃部位的镍铬基金属TiC陶瓷存在严重未烧结缺陷,成为起裂源;不合理的热处理工艺造成了刀具基体3Cr13晶粒粗大,并且沿晶界呈网状分布有脆性碳化物,导致基体脆性增加,在使用过程中发生沿晶断裂。

Fracture failure of a TiC ceramic cutter was studied from two views of optical microstructure and fracture analysis.It was revealed that there was serious unsintered defect in the cutter which acts as a fracture origin.Improper heat treatment leaded to coarse grain for 3Cr13 substrate.Brittle carbides distributed along grain boundaries,which resulted in great brittleness for its matrix.Therefore,fracture occurred very often during service.