23CrNi3Mo钢钎尾端部崩落原因分析

为了提高 23CrNi3Mo钎具钢的凿岩疲劳寿命，采用光学显微镜、扫描电镜、硬度计等方法对不同疲劳寿命下的 23CrNi3Mo钢钎尾端部崩落的形貌、显微组织、晶粒度、硬度分布进行分析。结果表明：端部崩落程度与凿岩寿命有一定的对应关系，凿岩寿命越长，崩落越严重，崩落发生在渗碳层到基体的过渡层。崩落的原因是材料达到疲劳强度。端部奥氏体晶粒度越细，渗碳后硬度高，凿岩寿命延长。

Cause analysis of end caving of the shank adaptor made by 23CrNi3Mo steel

To improve the drilling fatigue life of 23CrNi3Mo drill steel，themorphology，microstructure，grainsizeand hardness distribution of the end caving of the shank adaptor made by 23CrNi3Mo steel under different fatiguelife were analyzedby using optical microscopy，scanning electron microscopy and hardness testing machine. The results showed that the degree of end caving was corresponding to the drilling fatigue life，the higher the drilling fatigue life，the more serious the caving，and the caving occured in the transition layer of the carburized layer to the matrix. The reason for the caving was that the material reached the fatigue strength. The finer the grain size of the austenite atthe end，the higher the hardness after carburizing，and the longer the life of drilling fatigue.