Effect of TiO2 Content on the Arc-Erosion Resistance of Ag/SnO2 Electrical Contact Materials Prepared via Mechanical Alloying-Assisted Powder Metallurgy

Abstract In this study, the arc-erosion performances of AgSnO 2 -based electrical contact materials containing different amounts of titanium dioxide (TiO 2 ) were investigated using the mechanical alloying-assisted powder metallurgy method. For this purpose, composite powder synthesis was carried out through grinding experiments using a planetary ball mill, and the produced composite powders were subjected to molding and vacuum sintering processes. Subsequently, electrical wear tests were carried out under inductive loads to investigate the arc-erosion performance of composites. Scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), and laser diffractometry techniques were used to characterize powders, green compacts, composites and arc-affected surfaces. The results showed that the smallest composite powder size (1.186 µm) was obtained from samples containing 7% by weight of TiO 2 . Furthermore, it was determined that the green compacts containing 1% TiO 2 had the lowest porosity ratio (1.21%). In addition, the hardness values were observed to gradually increase from 82 HV to 112 HV with increasing TiO 2 content. It was also observed that the use of 5% TiO 2 improved the interfacial wettability between the matrix and reinforcement, thereby increasing the viscosity of the abraded material and reducing particle spatter. One of the key findings of the study is that, under test conditions of 220 V, 50 Hz, and 20 A, the addition of 5% TiO 2 reduced total mass losses by 46.78%.