Si元素对Al-40Zn-xSi钎料组织和性能的影响（英文）

Effects of Silicon on Microstructures and Properties of Al-40Zn-xSi Filler Metal

研究了Si元素对Al-40Zn-xSi钎料的钎焊性能,显微组织的影响以及不同Al-40Zn-xSi钎料对铝合金钎焊接头的显微组织和力学性能的影响。结果表明:当Al-40Zn-xSi中Si元素含量为4%(质量分数)时,钎料具有最好的润湿性能。显微组织分析表明:当Si元素含量超过4%后,钎料中开始出现块状初生硅;铝合金钎焊接头水冷后,Al-Si共晶组织和Zn-Al共析组织共存于焊缝中α-Al的枝晶间区域。当钎料中Si元素含量为4%时,焊后水冷的铝合金钎焊接头的抗剪强度达到最大值142.28 MPa。但是,当钎料中Si元素含量为5%以上时,焊缝中会形成较多的脆性共晶组织和初生硅颗粒,影响接头力学性能。

The effect of Si on the brazability and the microstructures of Al-40Zn-xS i filler metals were studied, and the microstructures and the mechanical properties of the joints brazed with Al-40Zn-xS i filler metals were investigated. The results indicate that the Al-40Zn-x Si filler metal presents the best wettability on 6061 aluminum alloy when Si content is and 4.0 wt%. The microstructure of the filler metal indicates that the primary silicon particles could be found when the silicon content exceeds 4.0 wt%. Al-Si eutectic mixed with Zn-Al eutectoid is located at α-Al interdendritic regions in the brazed seam after cooling with water. Moreover, the Al-40Zn-4Si joint possesses the optimum shear strength of 142.28 MPa. However, the excess of Si would increase the amount of brittle eutectic structure and primary silicon particles in the brazed joints, and thereby the mechanical properties will be deteriorated.