摘要
为了研究非金属夹杂物对钢内部显微组织形态的影响,利用金相显微镜、扫描电子显微镜、显微硬度计和扫描电镜EDS能谱仪对SCM-420机械结构用钢内部的夹杂物形貌、基体微观组织、失效断口进行了观察分析.研究结果表明:夹杂物主要为点状的氧化物-硅酸盐混合型、块状的氧化物型和条状的硅酸盐型;夹杂物的周围存在脱碳层,其显微组织为单相的铁素体;夹杂物与基体生成了类共晶组织;微裂纹以夹杂物和脱碳层为通道,导致SCM-420机械结构用钢的脆性断裂.
In order to study the effect of non-metallic inclusions on the microstructures of steel,the morphology of inclusions,microstructure of matrix and failure fracture surface of SCM-420 structural steel were observed and analyze with optical microscope（OM）,scanning electron microscopy（SEM）,micro-hardness tester and energy dispersive spectrometer（EDS） equipped on SEM.The results indicate that the inclusions are mainly dot-like oxide and silicate mixture,lumpish oxide and strip silicate.The decarburized layer is observed around the inclusions,and its microstructure is composed of single-phase ferrite.The eutectic-like microstructure forms due to the reaction between inclusions and matrix.The non-metallic inclusions and decarburized layer can be regarded as the channel of microcracks,which results in the brittle fracture of SCM-420 structural steel.
出处
《沈阳工业大学学报》
EI
CAS
2011年第5期520-523,539,共5页
Journal of Shenyang University of Technology
基金
国家自然科学基金资助项目(50671012)
关键词
非金属夹杂物
微观组织
断口
氧化物
硅酸盐
脱碳层
铁素体
类共晶组织
脆性断裂
non-metallic inclusion
microstructure
fracture surface
oxide
silicate
decarburized layer
ferrite
eutectic-like microstructure
brittle fracture
