预应变下建筑用高强钢焊接接头断裂性能研究  

Research on the fracture performance of welded joints of high strength steel used for building under pre-strain

作　　者：杨利辉[1] 

机构地区：[1]成都纺织高等专科学校,四川成都611731

出　　处：《电焊机》2014年第12期104-106,共3页Electric Welding Machine

摘　　要：对预应变下的建筑用高强刚Q420母材和焊缝进行拉伸、冲击和断裂韧度试验。实验结果表明:在预应变下,建筑用高强刚Q420焊缝与母材的冲击韧度都明显降低,韧—脆转变温度都明显提高;当材料的预应变加大时,其抗拉强度和屈服强度都明显提高,发生脆性断裂的可能性变大;当预应变为10%时,焊缝的韧—脆转变温度仍低于室温(20℃),可在室温条件下安全使用。该研究表明,预应变应作为材料使用安全分析的一个重要参考指标。The effects of pre-strain on the impact toughness of base metal and weld metal of High Strength Steel （Q420） used for building were investigated experimentally by use of The Charpy notch impact,tension and fracture toughness tests at different testing temperatures.The results of the tests show that：Under pre-strain,the impact toughness of both base metal and weld metal decreases,the ductile-brittle transition temperature increases,as the strain increases,both the tensile strength and yield strength increase,and the potential of the brittle fracture is higher,when the pre-strain is 10％,The range of ductile-brittle transition temperature of the weld metal is lower than the room temperature （20 ℃）,at which it can be used safely.The research shows that the pre-straining effect should be considered when carrying out effective safety analysis.

关 键 词：Q235B 预应变 焊接接头 

分 类 号：TG407[金属学及工艺—焊接]