挤压型银石墨焊料层气孔形成原因及改善对策

Formation Reason and Improvement Method of Stomata in Extrusion Silver Graphite Solder Layer

采用挤压法制备垂直纤维强化型银石墨产品,按常规混粉-等静压-烧结-挤压-切片-脱碳-切分覆焊料工艺,产品背覆焊料近银层区域有明显的气孔。比较增加3种不同温度的烧结以及增加脱碳层厚度对焊料层气孔的影响,研究结果表明,脱碳后增加烧结,烧结后银层内气孔孔径变小,覆焊料时,排入焊料层单个孔气量相对变少,不同温度对银点尺寸影响不同;增加脱碳层厚度,对焊料层气孔大小和数量无明显改善。

The vertical fiber reinforced silver graphite product was prepared by extrusion method.The conventional process is:mixing powder-isostatic press-sintering-extrusion-slicing-decarburization-cutting-solder coating and there are obvious pores near the silver layer of solder coating on the back of the product.Compare the effects of adding sintering with 3 different temperatures and increasing the thickness of decarburized layer on the porosity of the solder layer.The results show that the porosity in the silver layer is smaller through increasing sintering after decarburization,and the single pore gas discharged into the solder layer is relatively less when the solder is coated,and the silver spot size is affected by different temperatures.Increasing the thickness of the decarburized layer do not significantly reduce the size and number of pores in the solder layer.