Effects of Fe content on microstructure and properties of ferrous medium-entropy alloys prepared using powder metallurgy. (March 2023)

• Record Type: Journal Article
• Authors: He, Jichang; Ding, Xuekun; Li, Zhanjiang; Chen, Jia; Wang, Haiyan; Zhang, Mingrong; Xiang, Zhongnan; Dai, Pinqiang; Tang, Qunhua
• Is Part Of: Materials today communications. Volume 34(2023)
• Publication Date: 2023-03
• Subjects: Medium-entropy alloy -- Ferrous medium-entropy alloys -- Powder metallurgy -- Mechanical properties -- Friction and wear; Materials science -- Periodicals; 620.11
• DOI: 10.1016/j.mtcomm.2023.105344
• Languages: English
• ISSNs: 2352-4928

Abstract

Abstract: Herein, to reduce costs and improve the mechanical properties of medium-entropy alloys (MEAs), ferrous MEAs, Fex (CoCrNi)100−x (x = 55, 60, 65, and 70), were prepared via mechanical alloying (MA) and spark plasma sintering (SPS). The effects of the Fe content on the microstructure and mechanical properties of Fex (CoCrNi)100−x MEAs were investigated. The results showed that the structures of the Fex (CoCrNi)100−x (x = 55, 60, and 65) alloy powders were single face-centered cubic (FCC) solid solutions, and the structure of the Fe70 (CoCrNi)30 alloy powder belonged to a single body-centered cubic (BCC) solid solution after 35 h of MA treatment. After sintering at 1000 ℃, the tested alloys consisted of FCC and BCC phases with a small amount of the M7 C3 phase. With increasing Fe content, the BCC phase content increased, and the FCC phase content decreased, with a small amount of carbides (M7 C3, M=Cr or Fe). As the Fe content increased, the compressive yield strength and compressive strength of the alloy gradually increased. The strengthening mechanisms are mainly precipitation hardening, grain boundary strengthening and the increasing of BCC phase. The coefficient of friction and wear rate of the alloys decreased with increasing Fe content at room temperature. The wear mechanism was mainly abrasive wear accompanied by oxidative wear. This work provides a reference for the development of powder metallurgy ferrous materials. Graphical Abstract: ga1