摘要
采用热模拟试验模拟了单道次焊接Q690高强贝氏体钢焊接粗晶区热循环过程;研究了不同冷却时间(t_(8/5))下粗晶区的微观组织、冲击韧性、断口形貌和显微硬度。结果表明:当t_(8/5)≤10 s时粗晶区组织为板条贝氏体和粒状贝氏体,M/A岛含量较少,且呈细小片状和粒状,冲击韧性较高;t_(8/5)>10 s后粗晶区组织为粒状贝氏体,而且M/A岛含量增加和尺寸增大,为粗大的岛块状形貌,粗晶区的韧性严重恶化。
Thermal cycle process of welding coarse-grained region of Q690 high strength bainite steel under the single bead welding condition was simulated by using thermomechanical simulator. Microstructure, impact toughness, fracture morphology and mierohardness of coarse grained region at different cooling times (ts/s) were studied. The results show that when t8/s ≤ 10 s, coarse-grained region with relatively high impact toughness consisted of lath bainite and granular bainite, and fine flaky and granular M/A islands with relatively small amount were found; When t815 〉 10 s, microstructure of coarse-grained region evolved into granular bainite, the size and content of M/A islands increased obviously and changed into coarse block arid island morphology, and the impact toughness was severey worsened.
出处
《机械工程材料》
CAS
CSCD
北大核心
2012年第11期84-87,共4页
Materials For Mechanical Engineering
基金
山东电力集团公司科学技术项目(2010A-24)