IMPACT BEHAVIOR OF A STS 304 H SHEET WITH A THICKNESS OF 0.7 MM

Abstract

The objective of this paper is to investigate impact behaviors of a STS 304 H stainless steel sheet with a thickness of 0.7 mm in the fixed boundary condition through an impact experiment and a numerical analysis. In order to examine the influence of impact conditions, including the impact energy and the nose diameter of the impact head, on force-deflection curves, absorption characteristics of the impact energy, and fracture characteristics, several impact tests were performed using a drop impact testing machine with micro-processor based signal processing system. Through the observation of microstructures in the vicinity of the impact area using a scanning electron microscope, it was found that the orange peel defect and the intergranular fracture occur in the vicinity of the contact area of the impact head. Three-dimensional FE analysis was performed by a commercial code ABAQUS Explicit to investigate the influence of impact conditions on plastic strain distributions, stress distributions, and local deformation behavior in the specimen. The results of the FE analysis showed that the fracture of the specimen takes place when the plastic strain, the effective stress, and the plastic dissipation energy in the fractured area are approximately 0.42, 1525 MPa, and 1.83 J, respectively.