Phase Transformation and Aging Behavior of Al0.5CoCrFeNiSi0.2 High-Entropy Alloy

A second criterion for sigma phase formation in high-entropy alloys

“…This criterion successfully predicts sigma phase formation in a number of HEAs. [20,27,28] However, the VEC criterion alone is insufficient to describe the complete picture of sigma phase formation in HEAs. For example, many binary alloys do not develop the sigma phase even though they have the 'right' VEC-their binary phase diagrams simply do not predict so.…”

Effect of Heat Treatment on the Microstructure and Mechanical Properties of Plasma Cladded CoCrFeNiMn Coatings on Compacted Graphite Iron

“…Especially, the microhardness and compressive strength of the alloy reached 959±2 HV0.5 and 1790 MPa, severally, at associate hardening temperature of 1200 °C due to an increase in the proportion occupied by the diffusely distributed secondary phase. Zhang et al [29] investigated the changes in properties of Al0.5CoCrFeNiSi0.2 alloy subjected to aging treatment at 700-1100 °C. It was found that at aging temperatures below 1000 °C, the σ-phase precipitated between the dendrites, inflicting the alloy to exhibit important hardening and lower tensile strain; whereas higher than 1000 °C, the aging temperature made higher tensile strain than the as-cast one because of the disappearance of the dendrites and also the coarsening of the microstructure.…”

Effect of deep cryogenic treatment on the microstructure and mechanical properties of AlCrFe2Ni2 High-entropy alloy

“…High-entropy alloys (HEAs) were introduced in the 1990s [1,2] and overcame the limitations of traditional alloys and became popular due to their simple phase structure [3][4][5][6][7][8][9] and excellent mechanical properties [10][11][12][13][14][15][16]. Heat treatment of traditional as-cast alloys can eliminate internal structural defects and stresses and improve their properties [17][18][19][20][21][22]. Deep cryogenic treatment is a type of heat treatment that is widely used to study traditional alloys.…”