摘要
采用超声冲击处理方法对Q345B钢十字接头进行处理,对比分析了两种振幅下焊接接头疲劳寿命的变化.结果表明,在25μm振幅下焊接接头的疲劳寿命相较18μm振幅下焊接接头的疲劳寿命提高了4.3~7.6倍,从超声冲击处理后的宏观形貌、微观断口、冲击区域表层组织等方面比较分析了不同振幅下超声冲击疲劳延寿差异的原因,并建立有限元模型进行焊接温度场、应力场和超声冲击的数值模拟,将试验结果与有限元计算结果进行综合对比分析.结果表明,同等冲击条件下振幅越大,压应力层更深,试件表面压应力值更大.
The fatigue life of Q345B steel cross joint was treated by ultrasonic impact treatment,and the fatigue life of the welded joint under two kinds of amplitudes was compared and analyzed.The results showed that the fatigue life of welded joints at 25 micron amplitude is 4.3~7.6 times higher than that at 18 micron amplitude.The reasons for the difference of ultrasonic impact fatigue life extension under different amplitudes were compared and analyzed in terms of macro-morphology,micro-fracture and surface structure of impact area after ultrasonic impact treatment,and the finite element model was established to simulate the stress field of welding temperature field and stress field.By comprehensively comparing and analyzing the test results with the finite element calculation results,the results showed that the greater the amplitude,the deeper the compressive stress layer and the greater the surface compressive stress of the specimen under the same impact condition.
作者
白易立
王东坡
邓彩艳
龚宝明
BAI Yili;WANG Dongpo;DENG Caiyan;GONG Baoming(Tianjin University,Tianjin 300072,China)
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2019年第12期149-153,I0008,共6页
Transactions of The China Welding Institution
关键词
超声冲击
有限元法
残余应力
疲劳性能
ultrasonic impact treatment(UIT)
finite element method
welding residual stresses(WRS)
fatigue life