Effect of Boronizing on the Microstructure and Mechanical Properties of CoCrFeNiMn High-Entropy Alloy

Abstract

The CoCrFeNiMn high-entropy alloys were treated by powder-pack boriding to improve their surface hardness and wear resistance. The variation of boriding layer thickness with time and temperature was studied. Then, the frequency factor D0 and diffusion activation energy Q of element B in HEA are calculated to be 9.15 × 10−5 m2/s and 206.93 kJ/mol, respectively. The diffusion behavior of elements in the boronizing process was investigated and shows that the boride layer forms with the metal atoms diffusing outward and the diffusion layer forms with the B atoms diffusing inward by the Pt-labeling method. In addition, the surface microhardness of CoCrFeNiMn HEA was significantly improved to 23.8 ± 1.4 Gpa, and the friction coefficient was reduced from 0.86 to 0.48~0.61.

Thermodynamic and Ab Initio Design of Multicomponent Alloys Based on (Fe50Mn30Co10Cr10)-xBx (x = 0, 5, 7, 10, and 15 at.%)

“…The alloy Fe 20 Mn 20 Co 20 Cr 20 Ni 20 , also known as the Cantor alloy, solidifies in a single FCC phase, demonstrating exceptional mechanical properties, strength, and ductility at the same time, showing a notable gap concerning conventional alloys, inclusive at cryogenic temperatures [ 22 , 23 , 24 , 25 ]. Currently, the study of HEAs has focused on the addition of non-equiatomic quantities of elements, as well as the incorporation of interstitial elements such as C, N, and B, considering that the hardening of the alloys is influenced by these components, in addition to the main elements that comprise the solid solution [ 26 , 27 , 28 , 29 , 30 ]. Chmielak et al recently investigated the addition of C and in combination with N as interstitial elements in the CrMnFeCoNi alloy, focusing on its mechanical properties from 77 K to 673 K, microstructure, corrosion resistance, and wear resistance [ 27 ].…”

Achieving Excellent Strength-Ductility Balance in Single-Phase CoCrNiV Multi-Principal Element Alloy

“…Multi-principal element alloys (MPEA), as a novel type of metallic crystalline materials, have been attracting much attention in the materials research community [1][2][3][4][5][6][7]. The concept of MPEA offers significant compositional variability, enabling the alloy to activate multiple deformation mechanisms to achieve desired properties, such as high hardness [8], high strength [8,9], a remarkable strength-ductility synergy [10], exceptional oxidation resistance [11,12], excellent corrosion resistance [13], superior wear resistance [14], and high radiation resistance [15] and so on. In recent years, due to its advanced alloy design concepts and outstanding properties, MPEAs featuring a single-phase face-centered cubic (FCC) structure have garnered significant research interest.…”