CoCrFeMnNi high-entropy alloys reinforced with Laves phase by adding Nb and Ti elements
- PDF / 1,106,570 Bytes
- 10 Pages / 584.957 x 782.986 pts Page_size
- 9 Downloads / 182 Views
CoCrFeMnNi high-entropy alloys reinforced with Laves phase by adding Nb and Ti elements Gang Qin1, Zibo Li1, Ruirun Chen2,a) , Huiting Zheng1, Chenlei Fan1, Liang Wang1, Yanqing Su1, Hongsheng Ding1, Jingjie Guo1, Hengzhi Fu1 1
National Key Laboratory for Precision Hot Processing of Metals, Harbin Institute of Technology, 150001, Harbin, China National Key Laboratory for Precision Hot Processing of Metals, Harbin Institute of Technology, 150001, Harbin, China; and State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, 150001, Harbin, China a) Address all correspondence to this author. e-mail: [email protected] 2
Received: 28 August 2018; accepted: 20 November 2018
Laves phase plays a positive role in improving the strength of high-entropy alloys (HEAs); Nb and Ti elements have potential to promote Laves phase formation in some HEAs. For improving the strength of the face-centered cubic (FCC) CoCrFeMnNi HEA, a series of (CoCrFeMnNi)100xNbx (atomic ratio: x 5 0, 4, 8, 12, 16) and (CoCrFeMnNi)100xTix (atomic ratio: x 5 0, 2, 4, 6, 8, 12) HEAs were prepared by melting. The effects of Nb and Ti on the microstructure evolution and compressive properties of the CoCrFeMnNi HEAs were investigated. For (CoCrFeMnNi)100xNbx HEAs, the second-phase (Laves and r phase) volume fraction increased from 0 to 42%. The yield strength also increased gradually from 202 to 1010 MPa. However, the fracture strain decreased from 60% (no fracture) to 12% with increasing Nb content. For (CoCrFeMnNi)100xTix HEAs, the yield strength increased from 202 to 1322 MPa. The Laves phase volume fraction also increased from 0 to 27%. However, the fracture strain decreased from 60% (no fracture) to 7.5% with increasing Ti content. Addition of Nb and Ti has a good effect on improving the strength of FCC CoCrFeMnNi HEA.
Introduction In the past few years, high-entropy alloys (HEAs) have attracted considerable research attention because of their excellent mechanical properties and simple solid solution structure. Many materials scientists have conducted a lot of research in the fields such as forging [1, 2], heat treatment [3, 4, 5], alloying [6, 7, 8], casting [9, 10], and phase stability [11]. Since 2004, when they were first proposed independently by Yeh and Cantor [12, 13], HEAs have emerged as an important breakthrough in the traditional alloy design and have opened a new path for exploring new materials with excellent properties. The traditional alloy design involves selecting the major component based on a specific property requirement and then conferring secondary properties by using alloying addition without sacrificing the primary property [13]. Several similar methods had been used in the field of HEAs. He et al. investigated the alloying effect of Al on the phase structure, strength, and ductility of the CoCrFeMnNi HEA system and found that the Al element had potential to directly change the
ª Materials Research Society 2019
phase structure and mechanical properties of CoCrFeMnNi HEA [14]. The crystal struc
Data Loading...
