Microstructure and improved plasticity of (FeCoNi1.5CrCu)p/Al composites subject to adjusted deep cryogenic treatment (DCT)

• Published in: Journal of alloys and compounds Vol. 895; p. 162690
• Main Authors: Liu, J.Q., Wang, H.M., Li, G.R., Su, W.X., Zhang, Z.B., Zhou, Z.C., Dong, C.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 25.02.2022; Elsevier BV
• Subjects: Composite materials; Crack propagation; Cryogenic engineering; Cryogenic treatment; Deep cryogenic treatment (DCT); Fracture toughness; Liquid nitrogen; Mechanical properties; Metal-matrix composites (MMCs); Microstructure; Microstructures; Microwave sintering; Performance indices; Plastic properties; Residual stress; Mechanical properties; Metal-matrix composites (MMCs); Deep cryogenic treatment (DCT); Microstructures
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2021.162690

•The DCT promotes grain rotation and preferential orientation, inducing the transformation of the (111) and (200) crystal planes of the aluminum grains to the (220) crystal plane due to the released internal stress.•The preferential orientation increases the absorbed work (toughness), which macroscopically reflects the increase in plasticity.•The decrease in strength is due to the expansion of microcracks in HEAs particles. [Display omitted] This study aimed to reveal the effects of Deep Cryogenic Treatment (DCT) on the microstructure and mechanical properties of (FeCoNi1.5CrCu)p/Al composites. Precisely, the microwave sintering-prepared samples were soaked in liquid nitrogen to optimize the DCT parameter. The results demonstrated that the (111) and (200) crystal face indexes were induced by released internal stress during DCT to turn to (220). The preferential orientation plays a vital role in plasticity improvement. The compression experiments show that the plasticity of DCT 36 is greatly improved, reaching 142%, compared to the untreated sample. The macro performance shows that the cracks change from one-way to two-way propagation, and the fracture toughness of DCT 36 increased by 155.6% compared to untreated due to multi-system slip.