Effect of Ball Milling and Spark Plasma Sintering on Microstructure and Properties of Mn–Cu Based Damping Alloy

Abstract

In the present study, a Mn–Cu-based damping alloy with a nominal composition of Mn–25Cu–2Al was produced by ball milling and spark plasma sintering. The phase composition, microstructure, compactness, micro-hardness, damping capacity of these materials were systematically investigated. Experimental results show that the ball milling mixed particles are mainly composed of α-Mn and γ-Cu. The microstructure of the alloy sintered at 730°C is mainly composed of γ-MnCu, γ-CuMn and α-Mn. With the increase of sintering temperature, γ-CuMn and α-Mn gradually disappear by the mutual diffusion of Mn and Cu elements. During 850°C sintering, the alloy is mainly single γ-MnCu solid solution. At the same time, as the sintering temperature increases, the compactness and damping capacity of the alloys increases and the micro-hardness decreases.

Fig. 3 BSE images of the microstructures of the SPS730 (a), SPS770 (b), SPS810 (c) and SPS850 (d) alloys.