摘要
采用热模拟技术研究了X80级抗大变形管线钢焊接粗晶区组织、显微硬度和韧性的变化规律,分析了焊后冷却速度和粗晶区组织、性能之间的关系.结果表明,X80级抗大变形管线钢焊接粗晶区组织类型主要为铁素体和少量珠光体、粒状贝氏体、板条贝氏体和板条马氏体4种类型.焊接粗晶区软化是X80级抗大变形管线钢焊接面临的主要问题.当焊后冷却速度在15～30℃/s之间时,X80级抗大变形管线钢焊接粗晶区的强度、室温以及低温韧性匹配良好,组织以板条贝氏体为主.
The microstructure,microhardness and toughness of coarse grain zone for high-strain pipeline steel X80 were studied by means of welding thermal simulation.Influence of cooling rates after welding on the microstructure and properties of coarse grain zone were investigated.The results illustrated that there were mainly four types of microstructure in coarse grain zone of high-strain pipeline steel X80,which includes polygonal ferrite(PF) and a small quantity of pearlite,granular bainite,bath bainite and bath martensite.The softening in coarse grain zone is an ubiquitous problem for high-strain pipeline steel X80.While the cooling rate after welding was between 15 ℃/s and 30 ℃/s,the coarse grain zone was mainly composed of bath bainite,which has the better microhardness,charpy toughness at room temperature and-10 ℃.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2012年第9期93-96,117-118,共4页
Transactions of The China Welding Institution
关键词
大变形
管线钢
粗晶区
显微硬度
韧性
high-strain
X80 pipeline steel
coarse grain zone
microstructure
microhardness
toughness
