基于电磁压制的Ag-Cu-Ge钎料合金成形工艺

针对Ag-Cu-Ge系钎料难以加工成薄片的难题,利用电磁粉末压制结合液相烧结的成形工艺制备了钎料薄片,探究了不同压制电压及烧结温度对钎料薄片致密度和组织结构的影响,选用优化工艺下的钎料薄片对铜板进行焊接实验。实验结果表明:压坯致密度随着压制电压的提高而显著提升,当压制电压为2800 V时,压坯致密度达到最大值88.62%,而电压升高到3000 V时,锗粉颗粒内部开始产生裂纹甚至破裂;250℃烧结温度下烧结体出现了弹性后效现象,当烧结温度升高到400℃时,烧结体致密度增长率达到最大值2.63%,若温度继续升高,烧结体晶粒则出现粗化现象;最终当焊接温度为600℃时,焊缝组织均匀,与母材形成了较好的冶金结合,表现出良好的焊接性能,说明了该成形工艺用于制备钎料薄片的可行性。

Forming process of brazing alloy Ag-Cu-Ge based on electromagnetic compaction

For the difficult in manufacturing brazing filler metal Ag-Cu-Ge into thin sheet, it was investigated that the influences of dif-ferent pressing voltages and sintering temperatures on the density and microstructure of the brazing filler metal sheet produced by electro-magnetic powder pressing combined with liquid phase sintering. Then, the welding experiments were carried out on copper plate by an op-timized process. The results show that the compaction density increases with the increase of compaction voltage. When the pressing voltage is 2800 V, the billet density reaches the maximum value 88. 62%, while at the voltage of 3000 V, cracks and even fractures develop in the internal of germanium powder particles. Then, the elastic after effect appears in sintered body at the sintering temperature of 250 ℃, and the density reaches the maximum value 2. 63% at the sintering temperature of 400℃. As the temperature rises continually, the coarsening phenomenon appears in sintering body. When the welding temperature is up to 600℃, the weld structure is uniform with the base metal to form a good metallurgical combination to show good welding performance, and the forming process for the preparation of solder sheets is feasible.