(1. 哈爾濱工業(yè)大學(xué) 先進(jìn)焊接與連接國(guó)家重點(diǎn)實(shí)驗(yàn)室，哈爾濱 150001；
2. 哈爾濱工業(yè)大學(xué) 金屬精密熱加工國(guó)家重點(diǎn)實(shí)驗(yàn)室，哈爾濱 150001)
摘 要: 采用激光填絲釬焊方法進(jìn)行1.5 mm厚65%(體積分?jǐn)?shù))Sip/4032Al復(fù)合材料對(duì)接接頭的連接，研究不同工藝參數(shù)下的釬料潤(rùn)濕鋪展行為和焊縫成形特性，以及焊縫中共晶硅的形態(tài)變化規(guī)律。結(jié)果表明：接頭開V型坡口非常有利于焊縫的背面成形；光斑直徑為20 mm、激光功率高于1 500 W時(shí)焊縫成形容易控制；與激光熔焊相比，激光釬焊方法更適合于連接高比分Sip/4032Al復(fù)合材料。焊接熱輸入對(duì)Si元素的溶解、擴(kuò)散行為影響很大，因此，不同激光功率下，焊縫中硅元素可以板狀、多角狀、瓣?duì)畛跎琛鍡l狀共晶硅等多種形態(tài)出現(xiàn)。焊縫中心由于冷卻速度較慢，還形成了共晶團(tuán)組織，共晶團(tuán)內(nèi)部為均勻分布的短棒狀共晶硅。
關(guān)鍵字: Sip/Al復(fù)合材料；激光釬焊；硅結(jié)晶行為
（1. State Key Laboratory of Advanced Welding and Joining,
Harbin Institute of Technology, Harbin 150001, China;
2. National Key Laboratory for Precision Hot Processing of Metals,
Harbin Institute of Technology, Harbin 150001, China）
Abstract:Laser brazing method was used to join 1.5 mm thick 65% (volum fraction) Sip/4032Al composite butt joints. The wetting and spreading behavior of brazing filler metal, characteristics of weld shaping, and morphologies of eutectic silicon with different process parameters were investigated. The results show that the V-groove is favorable to the weld back shaping, the weld shaping is easy to be controlled when the spot diameter is up to 20 mm and the laser power is higher than 1 500 W. Compared with laser fusion welding, the laser brazing method is more suitable for joining high fraction Sip/4032Al composite. Weld heat input has great influence on Si dissolution and diffusion, so various silicon morphologies are found in the weld under different laser powers, including strip, polygonal，petal primary silicon and lath-shaped eutectic silicon. The eutectic cells are formed at the centre of weld because of the lower cool rate.
Key words: Sip/Al composite; laser brazing; silicon crystallization behavior
