EFFECT OF ROLLING PROCESS ON THE FORMABILITY OF PLASTIC DEFORMATION FORALUMINUM ALLOY(7020-T6).

Abstract

The aim of this research is to study the effect of plastic deformation of aluminum alloy (7020-T6) sheets metal with (10 mm) thickness by cold rolling process. The deformation ratios are (5 ,%10,%15 ,%20(%respectively from the original thickness. The sheets are prepared with dimensions (10 × 50×100 mm) and then passed through a pair of rolls with diameter of (50mm). The tension test is carried on specimens which manufacture according to (ASTM E8) standard for each forming ratio. The hardness and grain size of the specimens were measured and the microstructure was inspected in order to know the effect of plastic deformation ratio on them. Rolling process was contributed in improvement for the mechanical properties of the alloy are increasing for the all forming degree and the best ratio was (15%). The ratio (20%) lead to small cracks in the specimens, as it appears in microstructure pictures. The ratios (5% &10%) produce inhomogeneous deformation , is not usually a desirable situation, which is lead to high increasing in the values of pressure and force of roll. This often corresponding to sticking friction conditions. On the other hand, the ratios (15% & 20%)produce homogenous deformation.