Theoretical and experimental investigation of superplastic rolling process

Rolling play an increasingly significant role in forming process, very few studies have been devoted to the case of rolling superplastic alloy. This paper presents an investigation of symmetrical and unsymmetrical rolling process, which is of fundamental interest for forming processes. The prediction of the strain rate in the unsymmetrical rolling process is thus a challenging task. This paper has a novel discussion of symmetrical and unsymmetrical rolling of superplastic (lead-tin) eutectic alloy and with different range of rolling speed ratios and percentage reduction in thickness. It was found that the strain rate calculated experimentally was always greater than that calculated from theoretical considerations. Curling of the specimen as it leaves the rolls in the unsymmetrical rolling depends on the percentage reduction in thickness and on roll speed ratio.