Numerical and Experimental Investigation of the Effect of Strength of Aluminum 6061 Alloy on Thickness Reduction in Single-Point Incremental Forming

Abstract

Single-point incremental forming (SPIF) is a kind of incremental sheet forming that is significantly novel. This method involves the utilization of a computer numerical control (CNC) machine to control the path of a forming tool, which is produced by a computer-aided manufacturing program (CAM), as it stretches a metallic sheet to achieve a desired shape. Low patch output and customized parts are good candidates for this kind of technique. The aim of the present investigation is first to study the effect of Aluminum alloy 6061 strength on the thickness distribution and thinning ratio in SPIF and then select the optimal strength to ensure uniform thickness and minimize the thinning. In order to achieve this, two different strengths of Al 6061 sheets have been employed: One used in its original form and the other heat treated to change its strength. Specimens have been prepared using the SPIF procedure for a truncated cone with dimensions of 120 mm diameter and 40 mm depth; the forming slope is 50°, and Solid work program was used to create the tool path. The thickness reduction along the wall portions was analyzed employing the finite element method using Abaqus software, and the numerical results were experimentally confirmed, where the deviation ratio between simulation and experiment was 3% for sample 1 and 5% for sample 2. The findings manifested that the specimens exhibited a consistent distribution of thickness, and the maximum thinning ratio decreased from 30% to 28.5% as the yield strength decreased from 278 MPa to 68.7 MPa, respectively.