摘要
针对12%Cr铁素体不锈钢,利用光学显微镜、扫描电镜,对在不同焊接热输入条件下的显微组织种类进行观察,得出热影响粗晶区的组织变化规律;应用Thermal-cal软件,确定了12%Cr铁素体不锈钢在焊接热循环条件下发生相变的温度区间,以及微合金元素Ti和Nb的析出相图。给出在焊接热循环作用下,改善铁素体不锈钢焊接接头热影响区韧性的建议,即焊接热影响粗晶区存在适量的马氏体;钢中添加微量元素Ti可抑制粗晶区晶粒长大,其作用优于Nb。
Microstructures of 12% Cr ferritic stainless steel under different welding heat input conditions were observed by optical microscope and scanning electron microscope （SEM）. The change roles of the steel in coarse grained heat-affected zone （CGHAZ） were obtained. The temperature range where phase changes took place was determined by Software Thermal-cal, together with precipitate phase diagrams of microalloys Ti and Nb. Suggestions of improving ferritic stainless steel＇ s toughness in welded joint HAZ were given. The suggestions include that there is a moderate amount of martensite in welded joint HAZ; if adding a small amount of element Ti in the steel, it can restrain grain growth in the coarse grain zone. The restraint effect of Ti on the grain growth is better than that of Nb.
出处
《宝钢技术》
CAS
2007年第3期70-73,共4页
Baosteel Technology
关键词
铁素体不锈钢
HAZ
微合金化
ferritic stainless steel
heat affected zone
microalloying
