Impact of Heat Treatment on the Rubbing Behavior of Bump-Type Foil Journal Bearing

Abstract

Under low-speed or start/stop conditions, the rubbing of top foil in foil journal bearing (FJB) prompting the application of heat treatment to improve the rubbing behavior of the foil bearing. During heat treatment, various factors can influence the thermo-physical properties of foil. Therefore, the present study is carried out to analyze the impact of heat treatment variables on the rubbing behavior of FJB. To obtain it, bump-type FJBs are fabricated using SS 316 foil material with a corrugated die. Subsequently, experimental investigations of the developed bump-type FJB are conducted based on response surface methodology. The rubbing behavior of the FJB, including wear rate and surface roughness, is evaluated under various heat treatment conditions. The results indicate that both the wear rate and surface roughness of bump-type FJB decrease with increasing HT time duration. Furthermore, it is observed that the temperature distribution of the heated foil becomes more uniform with longer HT time durations. At the optimal HT variables of 500°C and 3 hours, the surface roughness and rubbing temperature of bump-type FJB are measured at 1.295 μm and 55.20°C, respectively. Additionally, the rubbing temperature of bump-type FJB is thoroughly evaluated.