Analysis and control of inclusion defects in 42CrMoA steel shaft
LI Xue-feng 1，2，ZHANG Xian-feng 1， ZHANG Xin-yao 1，2， WANG Shi-ning 1
1. Luoyang Ship Material Research Institute， Luoyang 471023， China； 2. Henan Key Laboratory of Technology and Application of Structural Materials for Ships and Marine Equipments， Luoyang 471023， China
Abstract：The internal defects were found during non-destructive testing in one 42CrMoA steel shaft after forging. The methods including macroscopic analysis， scanning electron microscope （EDS） observation， energy dispersive spectrum analysis （EDS）， metallographic examination， chemical composition analysis and mechanical property analysis were used to analyze the property and causes of defects as well as the influence on the shaft. The results showed that the defects inside of shaft were foreign inclusions， which mainly included the oxides of Al， Si， Ti， Ca， Mg， Na and K. The inclusions were composed of a small amount of furnace slag and protective slag as well as a large amount of composite inclusions which were formed by refractory materials from molten steel or liquid slag flushing. These foreign inclusions were concentratedly distributed in the center of the shaft. The testing results of chemical composition， endogenous inclusion， metallographic structure and mechanical property in other positions were normal. The foreign inclusions could be reduced by the measures such as optimizing the casting procedures and designing slag trap.
李雪峰， 张先锋， 张欣耀， 王世宁. 42CrMoA钢主轴内部夹杂缺陷分析与控制[J]. 物理测试, 2020, 38(4): 19-23.
LI Xue-feng， ZHANG Xian-feng， ZHANG Xin-yao， WANG Shi-ning. Analysis and control of inclusion defects in 42CrMoA steel shaft. PHYSICS EXAMINATION AND TESTING, 2020, 38(4): 19-23.
2020, Vol. 38 
