Microstructure and Mechanical Properties of Co32Cr28Ni32.94Al4.06Ti3 High-Entropy Alloy.

Jinquan Guo,Chaozhongzheng Tang,Huan Sheng Lai

doi:10.3390/ma15041444

Jinquan Guo, Chaozhongzheng Tang + Show 1 more

Open Access

https://doi.org/10.3390/ma15041444

Copy DOI

Abstract

High-entropy alloys have good application prospects in nuclear power plants due to their excellent mechanical properties and radiation resistance. In this paper, the microstructure of the Co32Cr28Ni32.94Al4.06Ti3 high-entropy alloy was researched using metallurgical microscopy, X-ray diffraction, and scanning electron microscopy. The mechanical properties were tested using a Vickers microhardness tester and a tensile testing machine, respectively. The results showed that Co32Cr28Ni32.94Al4.06Ti3 had a single-phase, disordered, face-centered, cubic solid-solution structure and was strengthened by solid solution. The alloy lattice parameter and density were estimated as 0.304 nm and 7.89 g/cm3, respectively. The test results indicated that the alloy had satisfactory mechanical properties with yield stress and tensile strength of about 530 MPa and 985 MPa, respectively.

Highlights

High-entropy alloys (HEAs) are a type of alloys which contain five or more principle alloying elements to stabilize solid solution phases by maximizing configurational entropy
It has been found that some HEAs have excellent mechanical properties [4,5], and excellent thermal stability [5], wear resistance [4,5,6,7], and irradiation resistance
In this paper, the microstructure and tensile properties of Co32Cr28Ni32.94Al4.06Ti3 were researched in order to better understand the microstructure and mechanical properties of CoCrNi HEAs

Summary

Introduction

High-entropy alloys (HEAs) are a type of alloys which contain five or more principle alloying elements to stabilize solid solution phases by maximizing configurational entropy. For transition HEAs, AlCoCrFeNiZrx is known to possess a BCC structure when x = 0 [9]; with an increase in the Zr content, the mechanical properties are significantly improved, because the phase composition of the alloy changes from an ordered BCC solid-solution phase to an ordered Laves + BCC phase. The phase composition of the AlCoCrFeNiBx alloy changes from a BCC phase to BCC + FCC two-phase solid solution with an increase in the B content; the hardness and fracture strength increase first and decrease [10]. CoCrFeNiWx is known to possess a single-phase structure for x = 0.2 [11]; the phase composition of the alloy changes from a single-phase to a hypoeutectic phase, and the mechanical properties are significantly improved when the W content is increased. In this paper, the microstructure and tensile properties of Co32Cr28Ni32.94Al4.06Ti3 were researched in order to better understand the microstructure and mechanical properties of CoCrNi HEAs

Experimental Materials and Methods

Results and Discussion

Conclusions