Performance optimization of Al-based bond matrix in metallic bond diamond wheel

Commonly used alloying elements, namely Cu, Zn, Mg and Mn, were selected to strengthen aluminum with AlSi₂₀ as the main component. The factors, each with three levels, were marked as A, B, C and D, respectively. The L₉(3⁴) orthogonal test scheme was developed. Al-based bonding matrix was prepared by hot pressing sintering. The effects of alloying elements on the properties of the matrix were studied by means of Archimedes drainage method, rockwell hardness test, three-point bending strength test and scanning electron microscope. Results show that the addition of alloy elements reduces the sintering temperature of AlSi₂₀ and promotes the densification of sintering. The influence of alloy elements on hardness is Mn>Zn>Cu>Mg. The influence of bending strength is Cu>Mn>Zn>Mg. In conclusion, the combination of A₁B₂C₂D₂ and A₁B₃C₃D₃ have high hardness and bending strength, whose matrices are closely tied to diamond. The fracture mode of binding agent is brittle fracture, which can improve the self-dressing ability of diamond grinding wheel.