摘要
将直径为12.5mm的82B盘条进行了9道次的拉拔实验,采用扫描电镜观察了不同应变量拉拔变形后82B盘条显微组织和夹杂物的演变情况,并研究了珠光体片层间距与拉拔应变量之间的关系。结果表明:82B钢显微组织中的珠光体片层间距随着应变量增大而逐渐减小;拉拔变形后的珠光体片层强烈扭曲,渗碳体片随着铁素体片的弯曲而变形,表现出良好的塑性变形能力;由于中心偏析形成的马氏体的塑性变形能力较差,在拉拔过程中发生碎化并最终与基体脱离;直径约为10μm的脆性夹杂物在拉拔过程中只是自身发生碎化,并未在夹杂物周围引起裂纹。
An experiment was carried out that an 82B wire rod of 12.5mm in diameter was drawn nine passes. The evolution of the microstructures and inclusions of the 82B wire rod were observed by SEM after drawing at different strain, and the relation between pearlitic lamellar spacing and the drawing strain was investigated. The results indicate that the pearlitic lamellar spacing decreases as the drawing strain increases. And the drawn pearlitic layer distorted strongly and lamellar cementite deform along with the bending of lamellar ferrite, so they show good capability of plastic deformation. Moreover, the martensite formed owing to centre segregation is broken to pieces because of its weak plastic deformation capability in the drawing process and finally breaks away the matrix. In contrast to this, although a brittle inclusion of 10μm in diameter has also been broken to pieces in the drawing process, the crack around the inclusion is not formed.
出处
《中国机械工程》
EI
CAS
CSCD
北大核心
2011年第22期2744-2748,共5页
China Mechanical Engineering
基金
江苏省高校自然科学研究计划资助项目(08KJD460012)
