(1. 哈爾濱工業(yè)大學(xué) 材料科學(xué)與工程學(xué)院 先進(jìn)焊接與連接國家重點實驗室，哈爾濱 150001；
2. 哈爾濱工業(yè)大學(xué) 電氣工程及自動化學(xué)院 自動檢測與過程控制系統(tǒng)研究所，哈爾濱 150001)
摘 要: 以鎂焊絲為填充材料，對鎂/鍍鋅鋼異種合金進(jìn)行單、雙光束激光熔釬焊試驗研究，分析不同工藝參數(shù)對焊縫成形的影響規(guī)律，獲得不同熱源作用方式下的界面形態(tài)規(guī)律及其對界面強(qiáng)度的影響。結(jié)果表明：采用單、雙光束進(jìn)行填絲熔釬焊均可獲得較滿意的外觀成形；單光束容易存在未釬合現(xiàn)象，焊接過程不夠穩(wěn)定，而雙光束具有更好的溫度分布，容易提高潤濕鋪展能力。剪切強(qiáng)度測試結(jié)果表明，單、雙光束最大的接頭效率分別達(dá)到30.9%和42.4%，焊趾處裂紋的存在是導(dǎo)致接頭失效的主要原因。
關(guān)鍵字: 鎂合金；鍍鋅鋼；熔釬焊；雙光束
（1. State Key Laboratory of Advanced Welding and Joining, School of Materials Science and Engineering,
Harbin Institute of Technology, Harbin 150001, China;
2. Institute of Automatic Detecting and Process Control System, School of Electrical Engineering and Automation,
Harbin Institute of Technology, Harbin 150001, China）
Abstract:The single and dual laser welding-brazing of AZ31 Mg alloy to DP980 galvanized steel was conducted with Mg filler wire. The effect of different parameters on the weld appearance was analyzed. Moreover, the interfacial pattern under different heat sources and its influence on the interfacial strength were obtained. The results indicate that good weld appearance can be achieved using both single and dual laser beam welding-brazing as filler wire. It tends to produce the lack of fusion defect by single-beam welding and the welding process is unstable. The dual-beam welding has much more uniform temperature distribution, so, the spreading-wetting ability is better than the former. The shear test results show that the highest joint efficiency of single-beam and dual-beam welding are 30.9% and 42.4%, respectively. The crack produced at the toe of weld after laser welding-brazing is the main reason for joint failure.
Key words: magnesium alloy; zinc-coated steel; welding-brazing; dual beam
