Experimental and Finite Element Studies of Stretch Forming Process for ASS 316L at Elevated Temperature

Abstract

Austenitic stainless steel 316 L grade is a material having extraordinary mechanical properties, low cost and easily available. This is the reason it was used in various industrial and nuclear applications. In the present work, ASS 316L nakazima specimens are stretched under hot forming conditions (750°C, 825°C and 900°C) at a constant strain rate (0.1s-1) along with three different orientations. These six types of nakazima specimens were used to know the formability behaviour of the material with the help of forming limit diagrams (FLD) obtained by the stretch forming process. A smaller change in Punch load and an increase in displacement were observed, which indicates the formability improvement of ASS 316L sheet metal with the increase in temperature. In addition, ABAQUS 6.13 computer code was applied for the prediction of formability from 750°C to 900°C. To improve the accuracy of the simulation, a number of integration points were accrued within the thickness direction, limiting dome height (LDH).The ductile fracture was observed from SEM images for all the temperatures. A close agreement was found between experimental and simulated results.