Al_(2)O_(3)陶瓷和316L不锈钢钎焊接头的组织与性能

Microstructure and properties of Al 2O3 ceramic and 316L stainless steel brazed joints

为了降低钎焊接头残余应力,采用AgCuTi-Cu-AgCuTi钎料对Al_(2)O_(3)陶瓷与316L不锈钢进行真空钎焊连接,分别研究了钎焊温度(820、850和880℃)及Cu箔厚度(0.05、0.1和0.2 mm)对Al_(2)O_(3)陶瓷/316L不锈钢钎焊接头组织和性能的影响。结果表明:当中间层Cu箔厚度为0.1 mm时,钎焊接头的组织为Al_(2)O_(3)/Cu3Ti3O+Ag(s, s)+Cu(s, s)+Cu3Ti/Fe2Ti/316L;随着钎焊温度升高(Cu箔厚度为0.1 mm),钎焊接头剪切强度出现先降低后升高的趋势,在880℃钎焊10 min保温后,接头组织分布较为均匀,剪切强度最大,为79.2 MPa。随着Cu箔厚度的增加(钎焊工艺为880℃保温10 min),促进了Cu-Ti金属间化合物的生成,Cu基固溶体增多,焊缝变宽,钎焊接头的组织较为均匀致密,剪切强度呈上升趋势,Cu箔厚度为0.2 mm时,接头的剪切强度最大,为148.8 MPa。与直接使用Ag-Cu-Ti钎料的钎焊接头相比(接头的剪切强度为54.3 MPa),采用Cu箔做中间层的钎焊接头的剪切强度明显更高。

In order to reduce residual stress in brazed joints,AgCuTi-Cu-AgCuTi filler metal was used to vacuum braze Al 2O3 ceramic to 316L stainless steel.The effects of brazing temperature(820,850 and 880℃)and Cu foil thickness(0.05,0.1 and 0.2 mm)on microstructure and properties of the Al 2O3 ceramic/316L stainless steel brazed joints were studied.The results show that when the thickness of the intermediate layer Cu foil is 0.1 mm,the microstructure of the brazed joint is Al 2O3/Cu3Ti 3O+Ag(s,s)+Cu(s,s)+Cu3Ti/Fe2Ti/316L.As the brazing temperature increases(Cu foil thickness is 0.1 mm),the shear strength of the brazed joints shows a trend of first decreasing and then increasing.After brazing at 880℃for 10 min,the microstructure distribution of the joint is relatively uniform,with the maximum shear strength of 79.2 MPa.As the thickness of Cu foil increases(the brazing process is brazing at 880℃for 10 min),it promotes the generation of Cu-Ti intermetallic compounds,increases the number of Cu based solid solutions,widens the weld,the microstructure of the brazed joint is more uniform and dense,and the shear strength shows an upward trend.When the thickness of Cu foil is 0.2 mm,the maximum shear strength of the joint is 148.8 MPa.Compared with brazed joints directly using Ag-Cu-Ti filler metal(with a shear strength of 54.3 MPa),the shear strength of the brazed joints using Cu foil as the intermediate layer is significantly higher.