摘要
采用光学显微镜、扫描电子显微镜、显微硬度计、室温拉伸等分析测试手段,研究了SS400焊接接头的显微组织和性能.结果表明:热影响区过热区晶粒粗大,显微组织主要为粗大的先共析铁素体,使过热区软化,引起焊接接头断裂;热影响重结晶区综合力学性能好,显微组织主要是均匀细小的铁素体+珠光体,且保留了母材轧制态的带状分布特征,实验过程中变形抗力增大,使得强度明显提高;SS400焊接接头拉伸断口形貌为韧窝状,韧窝形状大小不一,分布广泛,其中,大的韧窝尺寸较大且深度较深,为典型的韧性断裂.
Microstructures and properties of welded joint for SS400 steel have been investigated by using optical microscopy, scanning electron microscopy and tensile test. The results show that the grain is coarser proeutectoid ferrite in HAZ, which results in softening for the over heated zone. Thus, the welding joint will fracture more easily. Fine acicular ferrite and pearlite are major microstructures for the phase transformation and recrystallization zone remains the zonal distribution feature, which appears a better mechanical properties.There are many dimples distributed in welding joints, and the surface shows a typical ductile fracture mode.
出处
《广西科技大学学报》
2015年第4期32-35,共4页
Journal of Guangxi University of Science and Technology
基金
广西制造系统与先进制造技术重点实验室开放基金项目(13-051-09S10)资助
