摘要
采用化学成分分析、宏观和微观检验等方法对GCr15轴承钢连铸坯在步进式加热炉内加热过程中发生断裂的原因进行了分析。结果表明:断坯中存在较多沿奥氏体晶界分布的网状裂纹,晶界呈熔凝特征,晶界上有许多含硅、铝、铬和锰等的液滴状复合氧化物颗粒,断口附近的沿晶裂纹周围氧化脱碳严重,局部有粗大魏氏组织。这些特征表明加热炉局部存在温度过高现象,进而导致坯料晶界弱化,并且在坯料和步进梁构成的悬臂拉力作用下最终造成沿晶断裂。
The fracture reason of C, Cr15 bearing steel continuous casting billet burned in working beam furnace had been analyzed by means of chemical composition analysis, macro and microstructure test. Results showed that much pattern cracking, around which severe oxidize and decarburized structure and little coarse widmanstatten structure were found, distributed along austenite grain boundaries that had obvious fused feature and were inlayed by some gutta multiple oxide particle with the composition of Si, Al, Cr and Mn elements. The fracture of the billet was caused by overburning with high temperature in certain local area of the furnace which led to grain boundary weakness and then formed intercrystalline cracking with the pulling force between ingot and walking beam.
出处
《理化检验（物理分册）》
CAS
2009年第7期431-433,共3页
Physical Testing and Chemical Analysis(Part A:Physical Testing)
关键词
轴承钢
连铸坯
过烧
沿晶断裂
bearing steel
continuous casting billet
over-burning
intergranular fracture
