PENGARUH SHOTPEENING TERHADAP KEKERASAN DAN KEKASARAN PERMUKAAN

Abstract

Shotpeening is a cold working process used to modify mechanical properties of metals and
composites. This paper observes the effect of shotpeening of on hardness and surface roughness for stainless
steel. In the experimental, shotpeening process was shooting the steel shot into the surface using the
pressurized air. Steel shot used is SAE No. 230 with carbon steel material No. 230 diameter ± 700 μm. There
are three angles for shooting positions, i.e. angle of 0°, 25°, and 45°. The results of the hardness value
obtained at the position of 0° material with a shooting duration of 10 minutes resulted in an increase in the
value of surface hardness reaching 13,1% (164.13HB). Surface roughness was evolved into three roughness
stages along with the shotpeening duration. The stages are increasing, decreasing, and constant roughness.
The surface roughness value of Ra is 1.86μm at 2 min, then decreases Ra value 1.64μm in the duration of 6
min, and constant duration until 10 min. Increasing the surface hardness with the duration of spraying, and
surface roughness increases, decreases and is constant.