Ultrasonic assisted friction stir welding （UAFSW） is a recent modification of conventional friction stir welding, which adds ultrasonic energy directly into the friction stir welding area by the pin. In this study, ...Ultrasonic assisted friction stir welding （UAFSW） is a recent modification of conventional friction stir welding, which adds ultrasonic energy directly into the friction stir welding area by the pin. In this study, 2A12 aluminum alloy was welded by this process and conventional, respectively. The tensile tests, microstructure and fracture surface of FSW joint and UAFSW joint were analyzed. The research results show that the surface forming texture of ultrasonic assisted friction stir welding joint, compared with conventional, is finer and more uniform, showing metallic matte color. The grains are much finer in weld nugget zone, thermo-mechanically affected zone and heat-affected zone; S-phase particles size is much smaller and distribution is more homogeneous in the matrix. The tensile strength of UAFSW joint is 94. 13% of base metal, and the elongation is 11.77%. The tensile strength of FSW joint is 83.15% of base metal, and the elongation is 8.81%. The tests results reveal that ultrasonic vibration can improve the tensile strength and the elongation of welded joints.展开更多
采用不同的超声功率成功对6061-T4铝合金进行了超声辅助搅拌摩擦焊接试验。对所获得的超声辅助搅拌摩擦焊接接头的力学性能、微观组织和断口形貌进行了对比分析。结果表明,接头的抗拉强度随着超声功率增大而升高。超声功率为1.5 k W时,...采用不同的超声功率成功对6061-T4铝合金进行了超声辅助搅拌摩擦焊接试验。对所获得的超声辅助搅拌摩擦焊接接头的力学性能、微观组织和断口形貌进行了对比分析。结果表明,接头的抗拉强度随着超声功率增大而升高。超声功率为1.5 k W时,抗拉强度达到最大的221 N/mm2,继续增大功率抗拉强度下降,接头硬度在该功率下分布较为均匀。断后伸长率随功率增加而降低。前进侧边界在轴肩与搅拌针交汇处和搅拌针底部存在收缩的圆弧,而在前进侧边界搅拌针中间作用区域形成了稍有弧度的鼓胀。拉伸断口形貌随超声功率增大分别由较大较深的韧窝转变为较小较浅的韧窝、韧窝和准解理、准解理和解理等形貌。展开更多
为了研究超声的导入对FSW焊缝成型过程中缺陷的抑制作用,对2.5 mm 2219薄板铝合金进行常规搅拌摩擦焊(FSW)和超声辅助搅拌摩擦焊(UAFSW)试验,从焊接变形、孔洞缺陷、残余应力值以及显微组织等方面进行了对比分析。结果表明:在相同的焊...为了研究超声的导入对FSW焊缝成型过程中缺陷的抑制作用,对2.5 mm 2219薄板铝合金进行常规搅拌摩擦焊(FSW)和超声辅助搅拌摩擦焊(UAFSW)试验,从焊接变形、孔洞缺陷、残余应力值以及显微组织等方面进行了对比分析。结果表明:在相同的焊接参数下,超声的加入能够使得焊缝成型更美观,有效抑制焊接变形,降低残余应力值,减少焊缝孔洞、疏松等缺陷,提高焊缝质量稳定性。展开更多
文摘Ultrasonic assisted friction stir welding （UAFSW） is a recent modification of conventional friction stir welding, which adds ultrasonic energy directly into the friction stir welding area by the pin. In this study, 2A12 aluminum alloy was welded by this process and conventional, respectively. The tensile tests, microstructure and fracture surface of FSW joint and UAFSW joint were analyzed. The research results show that the surface forming texture of ultrasonic assisted friction stir welding joint, compared with conventional, is finer and more uniform, showing metallic matte color. The grains are much finer in weld nugget zone, thermo-mechanically affected zone and heat-affected zone; S-phase particles size is much smaller and distribution is more homogeneous in the matrix. The tensile strength of UAFSW joint is 94. 13% of base metal, and the elongation is 11.77%. The tensile strength of FSW joint is 83.15% of base metal, and the elongation is 8.81%. The tests results reveal that ultrasonic vibration can improve the tensile strength and the elongation of welded joints.
文摘采用不同的超声功率成功对6061-T4铝合金进行了超声辅助搅拌摩擦焊接试验。对所获得的超声辅助搅拌摩擦焊接接头的力学性能、微观组织和断口形貌进行了对比分析。结果表明,接头的抗拉强度随着超声功率增大而升高。超声功率为1.5 k W时,抗拉强度达到最大的221 N/mm2,继续增大功率抗拉强度下降,接头硬度在该功率下分布较为均匀。断后伸长率随功率增加而降低。前进侧边界在轴肩与搅拌针交汇处和搅拌针底部存在收缩的圆弧,而在前进侧边界搅拌针中间作用区域形成了稍有弧度的鼓胀。拉伸断口形貌随超声功率增大分别由较大较深的韧窝转变为较小较浅的韧窝、韧窝和准解理、准解理和解理等形貌。
文摘为了研究超声的导入对FSW焊缝成型过程中缺陷的抑制作用,对2.5 mm 2219薄板铝合金进行常规搅拌摩擦焊(FSW)和超声辅助搅拌摩擦焊(UAFSW)试验,从焊接变形、孔洞缺陷、残余应力值以及显微组织等方面进行了对比分析。结果表明:在相同的焊接参数下,超声的加入能够使得焊缝成型更美观,有效抑制焊接变形,降低残余应力值,减少焊缝孔洞、疏松等缺陷,提高焊缝质量稳定性。
