Study on the Machining of Duplex Stainless Steel and its Microstructure and Surface Roughness

Abstract

Duplex stainless steel (DSS) is a relatively new material which is replacing Austenitic steels in offshore and paper-pulp industries due to its excellent combination of mechanical and corrosion resistant property. In this investigation, the work piece material that was utilised was DSS 2205. The experiment is carried out using a vertical CNC milling machine that has three axes of movement. Carbide inserts of ISO grade and ISO geometry APMT1135-PA120 are the types of tools that are utilised for milling operations. To assess the surface roughness values (Ra) of the machined samples, a surface roughness tester with the model number SJ-201 from Surf test was utilised. The investigation of machined DSS specimens using scanning electron microscopy revealed that the surface topography of the machined samples was homogeneously produced with smaller grooves with side flow being seen on the machined surface. According to the outcomes of the experiment that compared cutting speed to roughness, the roughness value decreases proportionally to the increase in cutting speed. The variations of Feed Rate vs. Roughness showed that an increase in the roughness value occurs in conjunction with an increase in the feed rate. The correlation between the depth of cut and the roughness value revealed that the roughness value is directly proportional to the depth of cut.