Effects of precipitation hardening on cutting force, surface roughness and tool wear in turning of 15‐5PH stainless steel

Abstract

Abstract15‐5PH steel is a group of martensitic stainless steel which is strengthened by precipitation hardening. This paper is aimed to evaluate the effects of precipitation hardening on the machinability of 15–5PH. Machining was carried out at different feed rates and cutting speeds under heat treatment conditions H900 (meaning heat treatment at 900 °F) and H1150. The cutting force, work‐piece's surface roughness and tool wear were compared to the results of turning in solution condition. Scanning electron microscopy observation revealed that crater and flank wear were the main tool wear types in the turning of 15–5PH under the H900, solution and H1150 conditions. In addition, turning in the H900 condition causes defects such as “side flow” of the workpiece surface and “plowing” by the tool, compared to turning in the solution condition. The analysis of variance indicated that H1150 had the highest performance in reducing the cutting force, tool wear and surface roughness. The comparison between turning in H900 and solution conditions showed that the average cutting force and tool's flank wear in the H900 condition are 18 % and 11 % higher than solution condition, respectively. However, the mean roughness was 14 % lower under H900 than the solution condition.