Microstructure and mechanical properties of AlxSi0.2CrFeCoNiCu1 − x high-entropy alloys. (15th January 2016)

• Record Type: Journal Article
• Authors: Li, Cheng; Xue, Yunfei; Hua, Mutian; Cao, Tangqing; Ma, Lili; Wang, Lu
• Is Part Of: Materials & design. Volume 90(2016)
• Page Start: 601
• Page End: 609
• Publication Date: 2016-01-15
• Subjects: High-entropy alloys -- Spinodal decomposition -- Microstructure -- Strain rate -- Mechanical properties; Materials -- Periodicals; Engineering design -- Periodicals; Matériaux -- Périodiques; Conception technique -- Périodiques; Electronic journals; 620.11
• DOI: 10.1016/j.matdes.2015.11.013
• Languages: English
• ISSNs: 0264-1275

Abstract

Abstract: Al x Si0.2 CrFeCoNiCu1 − x ( x = 0.2, 0.4, 0.5, 0.6, 0.8, 0.9) high-entropy alloys (HEAs) were prepared using vacuum arc melting and injection casting. The microstructures, detailed phases, and strain rate-related mechanical properties of the alloys were investigated. The alloys changed gradually from FCC to coexisting FCC and BCC and then to a BCC solid solution with an increase in the Al content and a decrease in the Cu content. With the Al content increase, the alloys with FCC structures exhibited an increased yield stress but a decreased plasticity. However, the alloys with the BCC structure exhibited both increased strength and plasticity. The improved mechanical properties of alloys are attributed to the combined action of solid-solution strengthening, a decrease in compositional segregation, and fine-grain strengthening. Graphical abstract: Highlights: The HEA changed from FCC, to FCC and BCC, to BCC solid solution with increasing Al. Nano-scaled spinodal decomposition phase formed in both FCC and BCC structures. Strain-rate sensitivity seems to be more pronounced for the FCC structures.