Corrosion Properties of Cast Iron Ball Materials in Wet Grinding

Abstract

Abstract The influence of chromium addition to grinding media on corrosion rates of various chromium containing cast iron ball materials was investigated using Tafel plot DC polarization resistance measurements under abrasion in a quartzite slurry. The high chromium cast iron ball materials exhibited low corrosion rates at low and non-abrasive conditions, and the corrosion rates were increased markedly with rotation speed. Whereas corrosion rates of low chromium cast iron ball materials were high, indicating little dependence on rotation speeds. To understand the properties of surface films of ball materials as a function of chromium content, AC impedance measurements were made at various cathodic and anodic potentials. The high chromium cast iron ball materials exhibited high polarization resistance values at an applied potential of −0.05 V (vs SCE). The polarization resistance values obtained by DC polarization resistance and AC impedance methods were correlated.