摘要
采用模拟焊接热循环的方法,研究了HQ130高强度钢焊接热影响区粗晶区(CGHAZ)中组织性能的变化,并利用扫描电镜(SEM)、透射电镜(TEM)和电子衍射技术对焊接CGHAZ冲击断口形态和精细组织结构进行了分析。试验结果表明,HQ130高强钢焊接CGHAZ韧性下降的原因除了板条马氏体(ML)的粗化外,更重要的是上贝氏体(Bu)组织的形成。通过控制焊接线能量(E=10~20kJ/cm)使CGHAZ形成ML+(10~15)%BL组织,避免形成贝氏体(Bu+Bg)组织,可使该钢热影响区粗晶区韧性保持在较高水平上。
Microstructure and properties in the coarse grain heat-affected zone (CGHAZ) of HQ130 high strength steel were studied by using the welding thermo-simulation test. Fracture morphology and fine structure in CGHAZ were analysed by means of SEM、TEM and electron diffraction. Experimental results indicated that the important cause resulted in toughness decrease in CGHAZ is the formation of upper bainite ( Bu ) microstructure except the coarsing of lath martensite( ML ). By controlling welding heat input ( E =10~20 kJ/cm) to form mixed microstructure of ML +(10~20)% BL in CGHAZ, preventing to form bainite ( Bu + Bg ), toughness in the CGHAZ can be maintained at higher level.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
1998年第3期141-146,共6页
Transactions of The China Welding Institution
基金
山东省自然科学基金
关键词
高强度钢
CGHAZ
冲击韧性
焊接
TEM
high strength steel, simulated CGHAZ, impact toughness, microstructure