Microstructure and Mechanical Properties of WTaCrVTi High-Entropy Alloy Prepared by Mechanical Alloying and Spark Plasma Sintering

Abstract:

Mechanical alloying combined with spark plasma sintering (MA-SPS) was adopted to prepare W_23.5Ta_23.5Cr_23.5V_23.5Ti₆ high-entropy alloys. The effects of ball milling durations on the elemental distribution and microstructure of the alloys were explored. Results show that the powder after 40 h ball milling has a homogeneous particle size with 3.65±1.91 μm, and presents an equiaxed particle morphology. The dense and uniform alloy can be obtained after SPS at 1500 ℃. The WTaCrVTi_x solid solution with bcc structure is continuously distributed, in which the atomic ratios of W, Ta, Cr and V are close to the equiatomic ratios. A small amount of Laves phase is distributed in the matrix. The TiO particles with fcc structure have an average size of 1.08±0.38 μm and are uniformly distributed in the matrix. The room-temperature compressive yield strength, high-temperature compressive yield strength and microhardness of the alloy are 2870, 1954 MPa and 873.4 ±7.6 HV, respectively.