Probing the effect of abrasive wear on the grinding performance of rail grinding stones

Abstract

• Three grinding stones were fabricated individually using zirconia alumina, brown fused alumina and white fused alumina. • The main wear forms of rail grinding stones are blamed on attrition wear, abrasives pulled-out and fracture, the bond wear, material adhesion and clogging. • The grinding stones using brown fused alumina and white fused alumina exhibit better self-sharpness ascribed to the abrasives pulled-out and fracture. • The splintering mechanism of zirconia alumina is intergranular and transgranular fracture, while the brown fused alumina and white fused alumina are cleavable fracture. Grinding behaviour and wear mechanism of self-fabricated rail grinding stones (GS) using zirconia alumina (ZA), white fused alumina (WA) and brown fused alumina (A) were investigated in detail. The results illustrated that the grinding efficiency grew from GS-ZA and GS-A to GS-WA, and the GS-ZA gave the best ground rail surface quality. GS-ZA primarily consumed as attrition wear, while abrasive pull-out and fracture were dominant for the GS-WA and GS-A, thus making a better self-sharpness. The splintering mechanism of ZA was intergranular and transgranular fracture, and the macro-fracture and micro-fracture were presented by WA and A, respectively. Based on the experimental results, some suggestions about regulating the grinding performance of different GS, such as improving the grinding load of GS-ZA, reducing grinding heat of GS-WA, and the abrasive/bond interface modification of GS-A, were finally proposed.