Differential deformation during roll bonding of stainless-steel to aluminum sheet

Differential deformation during roll-bonding enhances solid phase welding, as the sliding at the interface promotes rupturing of the oxide films and exposes virgin metal. High differential deformation could be induced between stainless steel and aluminium sheet during roll-bonding by imposing geometrical and frictional constraint on the deformation of stainless steel(less than 10%).Thus a clad sheet with high residual ductility and small rela-tive thickness of stainless steel could be produced.

We measured the individual natural strain in stainless steel (es) and aluminium (Es) during composite rolling under different geometrical and frictional constraint. The differential strain (,N=es=es) first increases linearly with es and then becomes constant when a satisficto
bond has been obtained and the two metals deform together as a single piece. The slope of the de vs. es curves depends on geometrical frictional piramiters. I' was found that the greater the slope, lower is the deformation required for satisfactory bonding.