Joining Methods Applied to Sintered Aluminium Products

A major problem in the joining of dispersion-strengthened materials is to prevent destruction of the specific distribution of dispersed particles and thus avoid a decrease in high-temperature strength. The gas content may be another important factor since the presence of a large amount of gas in the material is likely to result in a porous welding zone. Different welding methods applied to sintered aluminium products are reviewed. Experiments related to the flash welding process and certain types of fusion welding are treated in more detail.
SAP-SAP joints of satisfactory high- temperature strength and tightness have been made by flash welding. In the special versions of fusion welding, sound joints are obtained by using aluminium as filler material under closely controlled conditions. As a consequence, good joint strength and tightness at elevated temperatures are achieved also by these methods when a suitable joint design is used.