A springback minimization study using the experimental design methods for 15-5 PH stainless steel material in the hydroforming process

Purpose This study aims to examine the springback behavior of 15-5 PH stainless steel, which is widely used in the aviation industry. Design/methodology/approach The shaping sheet metal with a diaphragm is a widely used shaping method in aviation. In this process, the sheet metal is attached to the mold, placed in the form machine and pressure is applied. The diaphragm, which swells under the influence of gas, transmits pressure to the sheet metal surface and allows the mold to take its shape. One of the behaviors that occurs in the part after processing is springback. The mold design is shaped according to this springing amount. Some prominent parameters in the amount of springback are bending radius, bending angle, material thickness and material type. Material thickness is taken as 0.813, 1.27, 1.6 and 2 mm for experimental studies. This study compares the general full factorial design with the 2k factorial design. Then, the authors get analysis of variance (ANOVA) tables for the experiments and finite element analysis results, respectively. Findings At the end of the study, a mathematical expression was obtained that gives the springback rate with an accuracy of over 90%, depending on the process parameters, in 15-5 PH material. In addition, the main effects of the working parameters on the springback behavior were revealed by ANOVA method. Originality/value To the best of the authors’ knowledge, this is a new application that provides robust results to the springback minimization for the sheet metal bending process.