Tungsten particles reinforced high-entropy alloy matrix composite prepared by in-situ reaction

Abstract

In this paper, a new preparation method of metal matrix composites is presented. The W/FeNiMnAlW high-entropy alloy (HEA) matrix composite materials have been prepared by a simple and efficient technology. The HEA matrix consists of a face-centered cubic (FCC) phase, an ordered body-centered cubic (BCC) phase and W2C phase. The volume fraction and average grain size of the reinforcing phase W particles, uniformly distributed in the microstructure of HEA matrix, are 30.9% and 13.57 µm, respectively. Good metallurgical bonding between W particle and matrix is achieved, and the formation mechanism of near spherical tungsten particles is discussed, and the density of the composites is 10.55 g/cm3. The hardness of W-phase, B2 phase and FCC phase was 681.48 HV, 533.82 HV and 286.70 HV, respectively. The yield strength (σ0.2) of the W/FeNiMnAlW composites is 1241 MPa, the maximum compressive strength (σmax) and the maximum plastic strain (εp) are over 2530 MPa and 15% respectively, which showed superior mechanical properties. The effective combination of FCC phase and ordered BCC phase and the uniform distribution of W particles without edges are the main reasons for its good mechanical properties. The volume wear loss and wear rate of the W/FeNiMnAlW composites are respectively 0.42 mm3 and 4.95 × 10−3 mm3/N m, and the worn mechanism is mainly adhesive wear and abrasive wear.