Experimental investigation on AISI 304 steel sheets formed by multi stage incremental forming

Abstract

Incremental sheet forming (ISF) is an sheet metal process which can be used widely in the area of automobile, medical and aeronautical application. The required shape of the final product is achieved by moving the rotating tool along the pre-determined path controlled by computer numerical controlled (CNC) milling machine. This paper explains the multi stage process to achieve the maximum wall angle in the cylindrical cup shaped component. The experiments were conducted using austenitic stainless steel AISI304 of 0.8mm thickness. In this work multi stage forming process was carried out in two stages (i). Starting from wall angle of 50° and (ii). Increasing the wall angle from 50° to 70° by keeping the tool traversing (1000 mm/min) and incremental depth (0.5mm) as constant for various tool rotational speeds of 600, 800 and 1000 rpm to maximum possible depth without the occurrence of fracture. In multi stage forming, with a wall angle of 70°, the maximum depth achieved was 21.3 mm before fracture at a tool parameters of 1000 rpm tool speed, 1000 mm/min tool traversing speed and 0.5mm incremental depth within the experimented process parameters.