材料期刊网

采用Al63-Cu22-Ti5-Si10钎料,研究了55%SiCp/6063Al复合材料和可伐合金之间的真空钎焊工艺,分析了钎焊温度和复合材料表面镀层材料对接头抗剪强度和显微硬度的影响规律,并对接头的显微组织进行了研究。结果表明钎焊温度和复合材料表面镀层对接头的力学性能影响很大,在同样的焊接参数下,复合材料表面镀铜的试样,其抗剪强度要高于无镀层和镀镍的试样,镀铜试样的最高抗剪强度为92.8 MPa。当钎焊温度从560℃增加到580℃时,接头的抗剪强度逐渐降低再上升,经过不同表面处理的试样均在钎焊温度为560℃时达到最大抗剪强度。钎焊温度相同时,镀铜试样的显微硬度均最高,而镀镍试样的显微硬度最低。焊缝组织致密,没有出现孔洞和未润湿等钎焊缺陷,钎焊完成后,接头中镀层被钎料取代而消失。在保温时间为30 min、真空度6.5×10-3 Pa条件下,采用Al63-Cu22-Ti5-Si10钎料,55%SiCp/6063Al复合材料与可伐合金真空钎焊合理钎焊温度为560℃,合理镀层为镀铜。

Using Al63-Cu22-Ti5-Si10 as brazing alloy, vacuum brazing between 55% vol. SiC particle reinforced aluminium matrix composites (55% SiCp/Al MMCs) and kovar alloy was investigated. The effects of brazing temperature and different plating material on the surface of SiCp/Al MMCs on joint shear strength and joint microhardness was analyzed, respectively. The microstructure characteristic of joint was studied as well. The results indicate that brazing temperature and plating material have significant influence on the joint mechanical property. With the same brazing processing parameters, the shear strength of specimen SiCp/Al MMCs covered by copper is much higher than those of covered by nickel and non-cover. The maximum shear strength can reach 92. 8 MPa. With the increasing of brazing temperature from 560 ℃ to 580 ℃, the shear strength decreases gradually and then increases. For the specimens with different plating material, the maximum shear strength of joint can be achieved at the brazing temperature 560 ℃. With the same brazing temperature, specimen covered by copper has the maximum microhardness and the specimen covered by nickel has the minimum microhardness. The microstructure of joint is quite dense and free from defects such as void and non-wetting area. After brazing, the plating metal has disappeared and it was replaced by brazing alloy. By using brazing filler alloy Al63-Cu22-Ti5-Si10 , the reasonable brazing temperature is 560 ℃ and the reasonable plating material is copper on the surface of composite under the parameters of vacuum degree 6 . 5 × 10 -3 Pa and soaking time 30 min.