Determination of Limit Drawing Ratio of SS 304 Steel using Sheet Hydroforming Process with Female Die

Abstract

Sheet hydroforming with female die process (SHF-D) is easily applicable without pressure and blank holder force control compared to the sheet hydroforming with punch process. Shallow parts can be produced easily with using SHF-D process which is used a lower cost production method in a wide variety of sectors. Limiting drawing ratio (LDR) is indication of formability of sheet metals is determined by using cylindrical punch die. In this study, for the first time, the LDRs of the SS 304 material with different thicknesses was determined experimentally by using the SHF-D instead of sheet hydroforming with punch unlike in the literature. Finite element analysis of SHF-D process has been realized. The results showed that relatively shallow sheet metal parts can be easily produced without the control of pressure and blank holder by means of SHF-D using obtained LDR. It is important to know the forming limit in the SHF-D, since it can be a more economical production method, especially in the manufacture of shallow and large parts used in the automotive and aerospace industries and obtain more quality products than that from classical deep drawing process. By knowing these ratios, die design and parts manufacturing can be realized less costly. The LDR was experimentally obtained as 1.82 with using the sheet hydroforming with female die for the SS 304. The FEA results are in good agreement with experimental results. So, it is useful to analyze the finite element method before designing the dies that will be used with the SHF-D.