(FeMnNi)84(AlTi)16 High-Entropy Alloy: Correlation of Microstructure, Strengthening Mechanisms and Hardness at Various Conditions (As-Cast, Solution Treated, Aged)

Abstract

A (FeMnNi)84(AlTi)16 high-entropy alloy was produced by vacuum arc melting successfully. The microstructure of the ascast state showed the existence of two FCC phases along with potential precipitates. The solution treatment response of the alloy for 2 h at 1150 °C and the effect of aging time at 750 °C in the microstructure and microhardness were also evaluated. It was observed that the solution treatment parameters were insufficiently low to dissolve the as-cast precipitates into the matrix. The double FCC matrix identified may be correlated with a solidification range and insufficient diffusion during the solidification process. The maximum hardness at 90 min aging time can be mainly attributed to the precipitation shearing mechanism in both matrix areas. The lower hardness value reported at 160 h aging time was estimated that it is derived by the change of the main strengthening mechanism from shearing to Orowan. The island-like precipitates that depleted Ti element from the Ni-rich intergranular area may be identified as a Ni2AlTi Heusler phase.

Effect of Aluminum Addition on the Microstructure, Magnetic, and Mechanical Properties of FeCrCoNiMn High-Entropy Alloy

“…HEAs have gained significant attention and are finding use in various industries and applications such as aircraft components, engine components, renewable energy, implantable medical devices, electronics, transportation (high-speed trains), additive manufacturing, etc. Several preparation methods were utilized to study the impact of the conditions parameters on the microstructure, magnetic, and mechanical properties of multicomponent HEAs alloys such as arc melting [6,7], induction melting [8], mechanical alloying (MA) [9,10], and laser additive manufacturing [11]. In arc melting, high-frequency electric arcs are used to melt and mix the constituent elements rapidly.…”