CAJ | 학술논문

为了研究超声辅助搅拌摩擦焊对焊缝残余应力的影响，试验应用20 kHz 的超声波辅助搅拌摩擦焊焊接了1.8 mm厚2024-T4铝合金，焊后应用X射线衍射法对焊缝的表面残余应力进行了测量，并与相同参数、工艺条件下搅拌摩擦焊残余应力进行对比。结果表明：转速1200 r/min、焊速160 mm/min时，超声辅助搅拌摩擦焊纵向残余应力比搅拌摩擦焊平均降低38 MPa(降低28.5%)。超声辅助搅拌摩擦焊沿焊缝方向各点纵向残余应力分布更加均匀化，波动量降低。超声辅助搅拌摩擦焊对焊缝横向残余应力影响很小，应力水平与搅拌摩擦焊相当。在相同转速下，随着焊接速度的提高，焊缝的纵向残余应力也随之提高。
위료연구초성보조교반마찰한대한봉잔여응력적영향，시험응용20 kHz 적초성파보조교반마찰한한접료1.8 mm후2024-T4려합금，한후응용X사선연사법대한봉적표면잔여응력진행료측량，병여상동삼수、공예조건하교반마찰한잔여응력진행대비。결과표명：전속1200 r/min、한속160 mm/min시，초성보조교반마찰한종향잔여응력비교반마찰한평균강저38 MPa(강저28.5%)。초성보조교반마찰한연한봉방향각점종향잔여응력분포경가균균화，파동량강저。초성보조교반마찰한대한봉횡향잔여응력영향흔소，응력수평여교반마찰한상당。재상동전속하，수착한접속도적제고，한봉적종향잔여응력야수지제고。
To investigate the effect of ultrasonic assisted friction stir welding (UAFSW) on residual stress of weld line, 1.8 mm thick 2024-T4 aluminum alloy plates were welded by UAFSW with 20 kHz ultrasonic, and the residual stress of UAFSW was measured by X-ray diffraction and compared with that of friction stir welding (FSW) under the same process parameters. The results indicate that when the stirring rate is 1 200 r/min and the welding speed is 160 mm/min, the longitudinal residual stress of UAFSW reduces 38 MPa compared with that of FSW on average, which is decreased by 28.5%. And the longitudinal residual stress along the weld line of UAFSW is much more even than that of FSW. UASFW has small impact on the transverse residual stress, which is nearly equal to that of FSW. The transverse residual stress increases as the welding speed increasing at a constant rotation rate.