摘要
低合金调质高强钢在焊接过程中,焊接接头会出现较严重的软化现象。采用维氏硬度计、光学金相显微镜及扫描电镜等测试方法,分析焊接接头区域的硬度及组织的变化,研究不同热输入和不同预热温度对调质态低合金高强钢焊接软化的影响。结果表明,不同热输入与不同预热温度下,软化区宽度与热输入或预热温度基本都呈线性关系。软化区域最低硬度值基本相同,其组织为铁素体和淬火马氏体的混合组织;随着热输入和预热温度的增加,铁素体长大,且边界越完整,而马氏体含量减少。
The welded joint generates more serious phenomenon in the welding process of low alloy quenched and tempered high strength steel. The hardness was measured by Vickers micro-hardness testing machine and the microstructure was studied by optical microscopy （OM）, scanning electron microscopy （SEM）. Based on the above analysis, the influence to the soften zone of the welded joint under different heat inputs or preheat temperatures was stuided, the experimental results show that the width of soften zone and heat inputs or preheat temperatures basically have a linear relationship. The lowest hardness of the soften areas are basically the same. The microstructure of the soften area is the mixture of ferrite （F） and martensite （M）. As the heat input or preheat temperature increases, ferrite grows up and the boundary becomes completely; the content of martensite decreases.
出处
《热加工工艺》
CSCD
北大核心
2013年第17期32-36,共5页
Hot Working Technology
基金
国家重点基础研究发展计划(973计划)项目(2010CB630800)
关键词
低合金调质高强钢
软化
热输入
预热温度
微观组织
quenched and tempered low alloy high strength steel
softing
heat input
preheat temperature
microstructure
