电弧堆焊作为一种低成本高效率的焊接方法在材料表面修复领域具有广阔的应用前景，文中将超声频脉冲电信号与低频交流TIG焊接电信号耦合，将超声能量引入TIG堆焊过程，改善铝合金TIG堆焊质量. 对超声频脉冲电信号耦合前后5083铝合金TIG堆焊焊缝成形、组织及硬度进行对比. 结果表明，随超声电源输出电压的增大，焊缝成形向熔宽减小、余高增大的趋势变化. 超声作用后，晶粒尺寸发生了一定变化，但晶粒形态无明显变化. 熔合区的晶粒细化最显著；焊缝区及热影响区的晶粒细化不明显，相反，随超声电源输出电压的增大，晶粒明显粗化. 熔合区及热影响区的第二相分布呈聚集现象. 超声作用对晶粒内部Mg元素的分布影响较大，增大超声电源输出电压，Mg元素在晶界处的偏析减弱. 硬度测试结果表明，超声频脉冲电信号耦合后焊缝硬度增大.
As a low-cost and high-efficiency welding method, arc overlaying welding has a broad application prospect in the field of material surface repair. In this study, ultrasonic energy is introduced into the TIG overlaying process to improve the welding quality of aluminum alloy by coupling the ultrasonic frequency pulse electrical signal with the low-frequency AC TIG welding electrical signal. The weld formation, microstructure, and hardness of overlaying welded joints of 5083 aluminum alloy were compared before and after implementing an ultrasonic pulse electrical signal. The results show that the weld formation changes towards the trend of decreased fusion wide and increased surplus height with the increase of the output voltage of the ultrasonic power. The grain size changs to some extent, but the grain morphology changs little after implementing the ultrasonic treatment. Grain refinement is the most significant in the fusion zone，but it is not obvious in the weld zone and the heat-affected zone. On the contrary, grain coarsening is obvious with the increase of the output voltage of the ultrasonic power. The distribution of the second phase in the fusion zone and the heat-affected zone shows an aggregation phenomenon. The ultrasonic effect has a great influence on the distribution of Mg element inside the grain. The segregation degree of Mg element at the grain boundary could be weakened by increasing the output voltage of the ultrasonic power. The hardness test results show that the weld hardness increases after coupling the ultrasonic frequency pulse electrical signal.
[1] Wang Y J, Wei B, Guo Y Y, et al. Microstructure and mechanical properties of the joint of 6061 aluminum alloy by plasma-MIG hybrid welding[J]. China Welding, 2017, 26(2): 58 - 63.
[2] Wang D Q, Hua C, Lu H. Numerical analysis of ultrasonic waves in the gas tungsten arc welding (GTAW) with ultrasonic excitation of current[J]. International Journal of Heat and Mass Transfer, 2020, 158: 1 - 10.
[3] Chen C, Fan C L, Cai X X, et al. Characteristics of arc and metal transfer in pulsed ultrasonic-assisted GMAW[J]. Welding Journal, 2020, 99(7): 203s - 208s.
[4] Fattahi M, Ghaheri A, Arabian N, et al. Applying the ultrasonic vibration during TIG welding as a promising approach for the development of nanoparticle dispersion strengthened aluminum weldments[J]. Journal of Materials Processing Technology, 2020, 282: 116672.
[5] Chen C, Fan C L, Liu Z, et al. Microstructure evolutions and properties of Al–Cu alloy joint in the pulsed power ultrasonic-assisted GMAW[J]. Acta Metallurgica Sinica (English Letters), 2020, 33(10): 1397 - 1406.
[6] Dong H G, Yang L Q, Dong C, et al. Improving arc joining of Al to steel and Al to stainless steel[J]. Materials Science and Engineering A, 2012, 534: 424 - 435.
[7] Watanabe T, Shiroki M, Yanagisawa A, et al. Improvement of mechanical properties of ferritic stainless steel weld metal by ultrasonic vibration[J]. Journal of Materials Processing Technology, 2010, 210(12): 1646 - 1651.
[8] Yuan T, Kou S, Luo Z. Grain refining by ultrasonic stirring of the weld pool[J]. Acta Materialia, 2016, 106: 144 - 154.
[9] 雷玉成, 崔展祥, 路广遥, 等. 超声电弧对6061铝合金MIG焊接头组织和性能的影响[J]. 焊接学报, 2020, 41(2): 33 - 38
Lei Yucheng, Cui Zhanxiang, Lu Guangyao, et al. Effect of arc-ultrasonic on the microstructure and properties of 6061 aluminum alloy joint with MIG welding[J]. Transactions of the China Welding Institution, 2020, 41(2): 33 - 38
[10] 吴敏生, 段向阳, 李路明, 等. 电弧超声的激发及其特性研究[J]. 清华大学学报(自然科学版), 1999, 39(6): 110 - 112
Wu Minsheng, Duan Xiangyang, Li Luming, et al. Study of arc-ultrasonic excitation and its characteristics[J]. Journal of Tsinghua University (Science & Technology), 1999, 39(6): 110 - 112
[11] He L B, Yang P, Li L M, et al. The ultrasonic characteristics of high frequency modulated arc and its application in material processing[J]. Ultrasonics, 2014, 54(8): 2178 - 2183.
[12] 张春雷, 吴敏生. 高频调制电弧超声发射及其物理特性[J]. 焊接学报, 2001, 22(1): 75 - 78
Zhang Chunlei, Wu Minsheng. High-frequency modulated arc as an ultrasonic generator and its physical property[J]. Transactions of the China Welding Institution, 2001, 22(1): 75 - 78
[13] Chen X Z, Shen Z, Wang J J, et al. Effects of an ultrasonically excited TIG arc on CLAM steel weld joints[J]. International Journal of Advanced Manufacturing Technology, 2012, 60(5-8): 537 - 544.
[14] Qi B J, Yang M X, Cong B Q, et al. The effect of arc behavior on weld geometry by high-frequency pulse GTAW process with 0Cr18Ni9Ti stainless steel[J]. International Journal of Advanced Manufacturing Technology, 2013, 66(9-12): 1545 - 1553.
[15] 许凯, 侯击波, 刘雅鑫, 等. 旋转磁场对ZL205A堆焊层组织与性能的影响[J]. 热加工工艺, 2019, 48(7): 69 - 72
Xu Kai, Hou Jibo, Liu Yaxin, et al. Influence of rotating magnetic field on microstructure and properties of ZL205A aluminum alloys surfacing layer[J]. Hot Working Technology, 2019, 48(7): 69 - 72
[16] Chen C, Fan C L, Cai X Y, et al. Analysis of droplet transfer, weld formation and microstructure in Al-Cu alloy bead welding joint with pulsed ultrasonic-GMAW method[J]. Journal of Materials Processing Technology, 2019, 271: 144 - 151.
[17] 陈琪昊, 林三宝, 杨春利, 等. 超声作用阶段及形式对熔池晶粒结晶的影响[J]. 焊接学报, 2020, 41(3): 29 - 32
Chen Qihao, Lin Sanbao, Yang Chunli, et al. Effect of different ultrasonic action stages on grain crystallization in TIG weld pool[J]. Transactions of the China Welding Institution, 2020, 41(3): 29 - 32
[18] 金礼, 徐敏, 薛家祥, 等. 热输入对铝合金双脉冲MIG焊接头性能的影响[J]. 焊接学报, 2018, 39(1): 89 - 92
Jin Li, Xu Min, Xue Jiaxiang, et al. Effect of line energy on properties of aluminum alloy joints in double pulsed MIG welding[J]. Transactions of the China Welding Institution, 2018, 39(1): 89 - 92
