Effects of cutting conditions on materials properties of austenitic stainless steels

Abstract

Austenitic stainless steel SUS304 is widely used in various engineering applications, including semiconductor manufacturing equipment and food processing machinery, owing to its exceptional material characteristics such as non-magnetic properties, high corrosion resistance, strength, and ductility. However, concerns have arisen in recent years regarding potential alterations in the material properties of austenitic stainless steel after machining processes. As the cutting process was conducted widely to make various engineering applications with different machining conditions, an examination of the effect of machining conditions on the material properties is important. In the present study, the influence of cutting conditions on the microstructure and mechanical of SUS304 was experimentally and numerically investigated, where three types of ball-end mills with rake angles (- 20°, − 3°, and 5°) and different cutting speeds (50 m･min⁻¹ and 100 m･min⁻¹) were conducted with plane and side machining to investigate the cutting properties. Material properties of SUS304 can be changed by the cutting resistance of the above cutting process, in particular the low rake angles under plane machining, where the high cutting resistance makes high dislocation density and strain-induced martensite formation. This occurrence made the low corrosion resistance as well as low ductility. On the contrary, no significant effect of the cutting speeds on the cutting resistance was detected compared to the condition of the rake angle on the plane machining. The reasons behind this will be discussed in detail systematically in this paper. From this approach, it could be clarified to maintain the high material properties of SUS304 even after the cutting process, which could be useful to make design of the engineering applications.