摘要
?16 mm 20Mn2线材在制作S形拉钩过程中断裂。对?13.5 mm S形拉钩断裂样品进行化学成分、金相组织分析。结果表明,断裂样品化学成分满足标准要求,金相组织为淬火马氏体,未见粗大晶粒,加工孔边缘存在晶界铁素体网。对断口进行扫描电镜分析,断面上存在明显的放射区,孔洞边缘存在沿晶断裂特征。S形拉钩在淬火过程中,由于淬火应力过大,在加工孔边缘产生应力集中,导致拉钩沿晶脆性断裂。
Abstract Diameter 16 mm 20Mn2 steel wire rod cracks in process of S-shaped hook production. Diameter 13.5 mm S- shaped hook fracture sample is chemical composition and micrnstrueture analyzed. Resuhs show that chemical eomposition of fracture sample meets requirements of standard, mierostructure is quenching martensite, without seen coarse grain size, grain boundary ferrite network exists in the edge of hole. The fracture is analyzed with SEM, obvious radiation field exists on fracture surface, intergranular fracture characteristic exists on hole edge. Stress concentration produced on edge of pro- cessing hole in process of quenching because of S-shaped hook too large quenching stress, causes hook intergranular brittle fracttnre.
出处
《金属制品》
2013年第5期56-59,共4页
Metal Products
