Experimental Investigation for Minimization of Spring back in L bending using Taguchi Design of Experiments

Spring back is a main defect occurred in the sheet-metal forming processes. In press working where sheet metal is given the required shape by using press, it is very much required to consider the variation in dimension after removal of the applied force. This work deals with analysis of spring back occurring in L- bending process of aluminium alloy. Comparison is made by varying various parameters like material thickness, rate of feed and settle time after bending. Various quality control tools like Taguchi analysis, ANOVA are applied to find most significant parameter affecting spring back obtained in L-bending process. Reverse bending technique is useful for minimization of spring back obtained in L bending. Efforts are made towards reducing the spring back using Reverse bending approach. The aim of the work is to identify various design parameters on which spring back depends and mainly focuses on experimental investigation of factors related to material and process parameters related to L-bending process using Aluminium (HE 9) which is commonly used for L-bending. These parameters include thickness, rate of feeding and time for which punch is kept in contact with specimen. Efforts are made towards minimisation of spring back using reverse bending tool.