Experimental investigations of Tribological properties of AISID3 Disc and TiN Coated Carbide Pin in LN2 Environment based on Taguchi Technique

Abstract

The effect of the supply of LN2 at the interface of TiN coated carbide pin and AISID3 disc for investigation of tribological properties was carried in the enclosed chamber on a pin on disc tribometer. Experiments were performed to compare tribological properties in dry run condition and the cryogenically cooled environment created by LN2. Design of experiments (DoE) was applied on the basis of L9 [OA] orthogonal array. Speed, load and distance were selected as three sliding parameters. Each was varied to three levels. The results were concluded by using Taguchi (signal-to-noise) ratio and analysis of variance techniques. Both the coefficient of friction and the specific wear rate lowered during cryogenic cooling with LN2 by 20-35% and 21-25% respectively as compared with the dry run condition. SEM microimages of worn-out pins were taken to understand the mechanism of wear. Abrasion and adhesion mechanisms were found during the dry run. SEM micro images of wear tracks showed abrasion and adhesion on low sliding parameters of speed, load and distance. Plastic deformation and fracture were found on high levels of sliding parameters of speed, load and distance. EDAX of wear tracks of high sliding parameters were taken during dry and cryogenic cooling with LN2. High peaks of Fe and O2 were found for both conditions. No traces of nitrogen were found during cryogenic cooling with LN2.