CASTING PROPERTIES OF HIGH-ENTROPY ALLOYS OF THE FeNiCrCuAl and FeNiCrCuMn SYSTEMS

Procesi littâ, 2024, Vol 4 (158), 56-65

Abstract

The article presents research on the casting properties of high-entropy alloys (HEAs) of the FeNiCrCuAl and FeNiCrCuMn systems. The HEAs were prepared by induction melting in air. The HEAs were smelted from different charge materials. At the beginning high-alloyed cast iron (content, wt.%: C = 2.60, Si = 1.80, Mn = 1.30, Ni = 17.00, Cr = 2.30, Cu = 3.60, S = 0.05, P = 0.07) and low-carbon ferrochrome of grade FeCr70C1 were loaded into the alumina crucible and then primary nickel with purity of 99.93 wt.%, copper wire of grade of Cu-ETP (purity 99.90 wt. %), technical grade aluminum ENAW-1085, Cu-Mn alloy (content, wt.%: Cu = 61.50, Mn = 37.70, and the balance Fe, Si,) and low-carbon ferromanganese (content, wt.%: Mn = 96.50, and the balance C, Si, S, P) were introduced into the melt. Experiments were carried out to study the castability and linear shrinkage of high-entropy alloys. For comparison, the casting properties of steels grades of C25E, GX10CrNiMn-18-9-1 and grey cast iron were determined. Various casting samples were used to study castability: an evaporative casting rod model, a cast iron U-shaped test sample of Nehendzi-Kuptsov with a vertical  channel, and a sand-clay mold with an annular channel. The temperature of the melt was monitored in the furnace, in the pouring basins, and directly in the castings. The cooling rates were determined in the temperature ranges between the liquidus and solidus on the cooling curves of the castings. It was established that the castability of the HEA of the FeNiCrCuMn system is lower than that of standard steels C25E, GX10CrNiMn-18-9-1 and significantly lower than that of gray cast iron. It was determined that the linear shrinkage of high-entropy alloys of the FeNiCrCuMn system is in the range from 2.22% to 2.63% and is close to the linear shrinkage of high-alloyed steels. Propensity to the formation of hot cracks was not found in the studied high-entropy alloys.