Experimental study of the effects of number of passes on mechanical properties, surface quality and spinning accuracy of aluminium 7075-O, during flow forming

Flow forming is an advanced eco-friendly chip-less metal forming process,which employs an incremental rotary point deformation technique. Flow forming offers a remarkable increase in tensile properties due to strain hardening and provides excellent dimensional accuracy and surface finish for the formed parts. In this study, effects of number of passes on mechanical properties, surface quality and spinning accuracy are investigated on 7075-O aluminium tube. A prototype tube spinning tooling has been designed and manufactured. The effect of number of passes on surface hardness, diameter growth, surface roughness, thickness variation and geometrical accuracy has been documented. The experimental results show that with increment of number of passes, the thickness variation increases but increasing feed rate has adverse effect on diameter growth and geometrical accuracy and it has no effect on surface roughness and surface hardness.

Keywords:

flow forming , tube spinning , aluminium 7075-O , number of passes