Effect of shot peening on microstructure, hardness, and corrosion resistance of AISI 316L

Abstract

Purpose: This research conducted to analyse the effect of shot peening on surface structure, hardness, and resistance to corrosion of AISI 316L. Design/methodology/approach: The shot peening process is carried out on the surface of 316L stainless steel samples with four peening durations, and they are 2, 4, 15, and 30 minutes. Shot ball steel with diameter 0.4 mm for metal shot blasting and model S110 of ISO 11124/3 and SAEJ827, with the chemical composition, are C (0.8-1.2 wt.%), Mn (0.6-1.2 wt.%), Si (min. 0.4 wt.%), S (max. 0.05 wt.%), P (max. 0.05 wt.%), with a hardness of steelball, about 40-50 HRC. The pressure of compressor kept constant at 8 bar with a diameter of the nozzle is 5 mm, and the distance between the nozzle and the sample surface variated by 6 cm and 12 cm for each shooting duration. Findings: The result shows that the shot peening increases the surface hardness of the material, changes the microstructure on the surface layer and increases the resistance to corrosion. Shot peening with 30 minutes of shooting duration and 6 cm of shooting distance can improve the metal surface properties, which has a surface hardness of 772.23 HV and good on corrosion resistance. Research limitations/implications: The results of this experiment show that shot peening distance of 6 cm for 30 minutes achieved the highest surface hardness of AISI 316L. The corrosion rate decline with increasing duration and nearer distance of shooting balls. Practical implications: In the development of the implant material, AISI 316L need to be improved, its material properties, so it can be used safely and compatibly. Shot peening is a cold working process of metal to increase the material properties by shooting the steel ball into the surface of a material. Originality/value: Based on the experimental results it was obtained that variations shot peening distance and shot peening duration can change grain morphologies, subsequently affect hardness and corrosion resistance on AISI 316L.