Superplastic forming and diffusion bonding of aluminium alloy

摘要

Superplastic forming and diffiusion bonding (SPF/DB) of Al-6Mg Alloy has beeninvestigated in this paper. Experimental resultsshow that the SPF/DB of aluminium alloy can besuccessfully realized if the grains of the alloyhave been refined to an average diameter lowerthan 10μm and the oxide film on the weldedsurface of the aluminium alloy can be effectivelyremoved by chemical corroding method. The optimumtechnique parameters were found to be: plasticforming temperatue is 450~500°C, pressure is0.5~2Mpa, and strain rate is 5~8×10-4 s-1,diffusion bonding temperature is 500°C, time is0.5~2h. The elemental duffusion behaviour at theinterface of the DB joints has been analysed byEPMA. The relationship between SPF and DB has beeninitially studied and it was concluded that theyare affected each other:SPF can improve theprocess of DB, and DB can decrease the structuredefects which formed during the plastic deformation.