铝与奥氏体不锈钢的火焰钎焊

为改善铝和不锈钢的焊接接头性能，在奥氏体不锈铜（1Crl8Ni9Ti）的表层热浸镀一层ZL102铝合金，然后采用搭接的形式，应用火焰钎焊工艺进行纯铝（1060）板与奥氏体不锈钢板的焊接。利用金相显微镜和扫描电镜分析焊接接头的微观组织，并用显微维氏硬度仪和万能实验机床测定其显微硬度和拉伸性能。结果表明，通过不锈钢表面热浸镀铝，可实现铝与奥氏体不锈钢的火焰钎焊。在不锈钢／纯铝钎焊焊缝中存在不锈钢／热浸镀铝层、热浸镀铝层／钎缝、钎缝／纯铝三个界面。钎焊接头强度取决于各界面的连接质量。热浸镀铝层／钎缝界面是整个接头中最薄弱的界面，剪切断裂均发生在该区域。钎焊接头各区域中，热浸镀铝区硬度最高，达到99．4MPa。

Flame brazing of aluminum to austenitic stainless steel

This paper aims at improving the performance of welded joints of aluminum and stainless steel. The improvement involves hot-dip coating of ZL102 aluminum alloy on austenitic stainless steel （ 1 Crl 8Ni9Ti） surface, followed by welding of pure aluminium plate （1060） and austenitic stainless steel plate using overlapping forms and applying flame brazing. Both analysis of the microstructure of welded joints using optical microscopy and scanning electron microscopy, and test of machine measured hardness and tensile properties using micro Vickers hardness tester and universal suggest that flame brazing is pos- sible with the stainless steel surface by hot-dip aluminum, aluminum and austenitic stainless steel. In stainless steel/aluminum brazing seam, there exist three interfaces, such as stainless steel/hot dip alumi- nized layer, hot dip aluminized layer/solder joints, and brazing seam/aluminum. Brazed strength depends on the quality of the connection interface. Hot dip aluminized layer/braze interface is the weakest inter- face connector, where shear fracture occurs. Of all areas of brazed joints, hot dip aluminized area shows the highest hardness, up to 99.4 MPa.