In the present work, a WC particle-reinforced CoCrFeMnNi high-entropy alloy (HEA) was fabricated by laser melting deposition (LMDed). The LMDed CoCrFeMnNi high-entropy alloy (CoCrFeMnNi) composite is primarily comprised of a face-centered cubic (FCC) crystal structure. However, in the case of CoCrFeMnNi with 2.5 wt.% WC, it exhibits a combination of an FCC matrix and a ceramic phase known as M₂₃C₆. The corrosion behavior of CoCrFeMnNi and CoCrFeMnNi with 2.5 wt.% WC particle in 0.5 M H₂SO₄ was comparatively investigated. Compared with CoCrFeMnNi, the passive film formed on the CoCrFeMnNi with 2.5 wt.% WC had a more stable and stronger protective property. The corrosion current density of the CoCrFeMnNi with 2.5 wt.% WC dropped by 149.1% compared to that of the CoCrFeMnNi, indicating that the CoCrFeMnNi with 2.5 wt.% WC had better corrosion resistance than that of the CoCrFeMnNi.

Because wear is one of the most common reasons for the failure of metals, the development of a low-cost coating with enhanced wear resistance is of great importance. In the present study, Fe–Si–Al coatings with superior and stable wear resistance were prepared by laser cladding Fe–Si–Al industrial waste onto 1045 carbon steel. The microstructure, as well as the wear mechanism of the Fe–Si–Al coatings, was investigated. The Fe–Si–Al coatings consist of a (Al, Fe, Si) solid solution phase in both columnar grain form and equiaxed grain form. The Fe–Si–Al coatings possess enhanced microhardness of 494 ± 15 HV_0.3 and low mass loss of 5 × 10⁻⁵ mg·(N·m)⁻¹. The wear resistance is ten times higher than that of the 1045 carbon steel matrix. The wear of the Fe–Si–Al coatings is mainly dominated by abrasive wear and adhesive wear. This work provides important insight into the preparation of low-cost, wear-resistant coatings, as well as stable, superior wear resistance.

Eutectic multi‐principal element alloys (EMPEAs), with multiple main elements in compositions and eutectic microstructures, are considered promising high‐performance materials for structural applications. The microstructure of EMPEAs usually exhibits a mixture of soft and hard phases in straight rod‐like or lamellar morphology, which contribute to a balanced synergy of strength and ductility. However, such conventional morphology may also constrain the possible space for further improving their mechanical properties, and the question proposed is whether the straight morphology can be kinked to unlock a new space for achieving better mechanical properties. Here an (AlCrFe ₂ ) ₆₅ Ni ₃₅ EMPEA featuring an unseen kinked vermicular eutectic microstructure is successfully prepared. This innovative microstructure imparts remarkably improved strength‐ductility synergy to the EMPEA, which surpasses both its coarse‐grained counterpart and typical EMPEAs with straight morphologies, indicating a pronounced strengthening of the vermicular eutectic microstructure. The phase‐field simulation reveals the formation of such microstructure as the lack of crystallographic locking caused by the similar elastic modulus of the two eutectic phases. The findings not only expand the family of possible eutectic microstructures but also offer a pioneering paradigm for enhancing EMPEAs, paving the way for their application in high‐performance structural materials.

In this paper, a laser-based directed energy deposition (DED) technique is used to fabricate FeCoNiCr and CrMnFeCoNi multi-principal-element alloys (MPEAs). Comparing the above samples, the FeCoNiCr samples with coarse columnar grains cracked, while the CrMnFeCoNi samples with equiaxed grain were crack-free. The strategy that removes cracks is to induce a columnar-grain-to-equiaxed-grain transition (CET) with Mn addition to offer more grain boundaries to withstand residual stress in the process of DED-fabricated FeCoNiCr and to help minimize hot cracking. Furthermore, the yield strength, tensile strength, and tensile ductility of the DED-fabricated CrMnFeCoNi obviously improved compared with the DED-fabricated CoCrFeNi and exhibited better isotropic mechanical properties. The present work provides a novel strategy to utilize CET for resisting crack propagation in the process DED-fabricated MPEAs and improvement in mechanical properties of MPEAs.