A comparative study on FeAl and NiAl bonded diamond tools for dry grinding based on wear characteristics at elevated temperature

Abstract

Dry grinding is considered an environmental-friendly machining process to reduce the utilization of coolant consisting of a complex mixture of chemical components and water. Thus, high mechanical properties at elevated temperatures are necessary for the metal bond diamond tools in dry grinding hard and brittle material, such as ceramics and stones. In the present study, the preparation of FeAl and NiAl by reactive sintering is proposed as the bond of diamond tools for dry grinding. The compressive properties and wear characteristics of FeAl and NiAl are compared at elevated temperatures. Furthermore, the diamond tools based on FeAl and NiAl are prepared, and their dry grinding performance on Si3N4 ceramic is examined. The results reveal that FeAl is characterized by higher compressive yield strength than NiAl at temperatures between 400 °C and 800 °C. Compared to NiAl, FeAl exhibits a higher friction coefficient, wear resistance, and a higher tendency to react with Si3N4 to increase adhesion. Hence, in dry grinding of Si3N4 ceramic, the FeAl-bonded diamond tool produces a higher grinding ratio, higher grinding force and temperature, and slightly lower surface roughness than NiAl.