超声冲击对转向架用16MnR钢焊接接头疲劳性能的影响

The Effect of Ultrasonic Impact on the Fatigue Properties of 16MnR Steel Welded Joints for Bogie

采用HJ2—Ⅱ型超声冲击枪,对转向架用16MnR钢的焊接接头表面进行超声冲击处理。利用EHF-EM200K2-070-1A疲劳试验机,采用较低载荷频率(低于10Hz)对16MnR钢焊接接头超声冲击前后的疲劳性能进行对比试验。试验结果表明:在疲劳寿命为2×106时,焊接接头试样在超声冲击处理前后的疲劳强度分别为265和325MPa,提高了22.6%;超声冲击处理后焊接接头的疲劳寿命是处理前的51～59倍。经过超声冲击处理后,焊接接头焊趾处的应力集中程度和焊接残余应力降低,表明超声冲击处理对提高16MnR钢焊接接头疲劳性能具有显著的效果。

The ultrasonic impact treatment on the surface of the welded joints of 16MnR steel for bogie was carried out by using HJ2—Ⅱ type ultrasonic impact machine.The fatigue tests were performed on the welded joints of 16MnR steel both in the welded and treated conditions to compare its fatigue properties by using EHF-EM200K2-070-1A type fatigue tester at lower load frequency（less than 10 Hz）.The experimental results indicate that when the fatigue life is 2×106,the fatigue strength of the welded joint specimen before and after ultrasonic treatment is about 265 MPa and 325 MPa,respectively.The fatigue strength of the welded joints has been increased 22.6%,and the fatigue life has been increased 51~59 times after ultrasonic impact treatment.The stress concentration and welding residual stress at the toes of the welded joints can be significantly reduced by using ultrasonic impact treatment,which indicates that the ultrasonic impact treatment has remarkable effect on improving the fatigue properties of 16MnR steel welded joints.