Hybrid Incremental Forming: Investigation on Localized Thinning and Thickness Distribution in Formed Parts

TLDR: In this article, a hybrid incremental sheet forming (HISF) process comprising stretch forming followed by single point incremental sheet formation (SPIF) is developed for forming conical frustum.

Abstract: In the present experimental work, hybrid incremental sheet forming (HISF) process comprising stretch forming followed by single point incremental sheet forming (SPIF) is developed for forming conical frustum. Experimental investigation is done to find the influence of process parameters on thickness distribution and localized thinning in the formed parts. Experimental result reveals that stretching has a substantial effect on localized thinning in formed parts. Small improvement in the thickness distribution and localized thinning is found in formed parts. Experimental investigation on the influence of preform tool shape is also done to further improve thickness distribution. It is observed that the geometry of preform tool and amount of stretching has a great influence on thinning and thickness distribution. It is found that intermediate preform tool size and small amount of preforming results in forming conical frustum having uniform thickness distribution. Also, a considerable reduction in forming time using developed HISF process is observed as compared to SPIF process alone.