Strengthening mechanisms, hardening/softening behavior, and microstructure evolution in an LPSO magnesium alloy at elevated temperatures

Wang, Jie1,2; Zhu, Gaoming1,2; Wang, Leyun1,2; Zhang, Xianbing3; Knezevic, Marko4; Zeng, Xiaoqin1,2

2023-09-01

10.1016/j.matchar.2023.113066

MATERIALS CHARACTERIZATION   影响因子和分区

1044-5803

1873-4189

Rapid degradation of the mechanical properties of conventional Mg alloys with temperature precludes their wide application in industry. The LPSO (long period stacking ordered) Mg alloys, on the other hand, show considerable potential to achieve excellent high-temperature mechanical performance. In this study, a Mg-5.1Y-2.4Zn (wt.%) extrusion alloy with the microstructure comprising of & alpha;-Mg matrix and LPSO phase was prepared. It is shown that the yield strength of the alloy at 200 & DEG;C retained -83% of the yield strength of 198 MPa at room temperature (RT). Importantly, the ductility also improved, owing to the increased non-basal slip activities at elevated temperatures. In contrast to RT and 200 & DEG;C, the alloy exhibited softening tensile behavior with an apparent loss of yield strength at 300 & DEG;C. In-situ lattice strain analysis revealed that load transfer from & alpha;-Mg to LPSO remains effective at temperatures up to 200 & DEG;C, governing the high yield strength of the alloy. The postmortem analysis by means of electron microscopy confirmed that the LPSO phase is structurally stable at 200 & DEG;C. In particular, the high strain hardenability is rationalized by the sandwiched LPSO structures together with stacking faults serving as effective obstacles to the motion of non-basal dislocations. The load transfer effect disappears at the temperature of 300 & DEG;C, resulting in the fast deterioration of strength of the alloy. The cracking of the LPSO phase along with the recrystallizing of & alpha;-Mg grains were found to be the main causes for the softening behavior of the alloy at 300 & DEG;C.

Magnesium alloys Elevated temperature strength Tensile deformation In -situ synchrotron X-ray diffraction Long -period stacking ordered structure

SCI ; EI

英语

其他

National Natural Science Foundation of China[51825101] ; United States Department of Energy, Office of Science, Office of Basic Energy Sciences[DE-AC02-06CH11357]

Materials Science ; Metallurgy & Metallurgical Engineering

Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering ; Materials Science, Characterization & Testing

WOS:001021722300001

ELSEVIER SCIENCE INC

20232514260652

Deterioration ; Magnesium alloys ; Microstructure ; Room temperature ; Tensile strength ; Ternary alloys ; Yttrium alloys ; Zinc alloys

Magnesium and Alloys:542.2 ; Zinc and Alloys:546.3 ; Alkaline Earth Metals:549.2 ; Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals:549.3 ; Thermodynamics:641.1 ; Materials Science:951

MATERIALS SCIENCE

Web of Science

1.Shanghai Jiao Tong Univ, Natl Engn Res Ctr Light Alloy Net Forming, Shanghai 200240, Peoples R China
2.Shanghai Jiao Tong Univ, State Key Lab Met Matrix Composites, Shanghai 200240, Peoples R China
3.Southern Univ Sci & Technol, Dept Mech & Energy Engn, Shenzhen 518055, Peoples R China
4.Univ New Hampshire, Dept Mech Engn, Durham, NH 03824 USA

Wang, Jie,Zhu, Gaoming,Wang, Leyun,et al. Strengthening mechanisms, hardening/softening behavior, and microstructure evolution in an LPSO magnesium alloy at elevated temperatures[J]. MATERIALS CHARACTERIZATION,2023,203.

Wang, Jie,Zhu, Gaoming,Wang, Leyun,Zhang, Xianbing,Knezevic, Marko,&Zeng, Xiaoqin.(2023).Strengthening mechanisms, hardening/softening behavior, and microstructure evolution in an LPSO magnesium alloy at elevated temperatures.MATERIALS CHARACTERIZATION,203.

Wang, Jie,et al."Strengthening mechanisms, hardening/softening behavior, and microstructure evolution in an LPSO magnesium alloy at elevated temperatures".MATERIALS CHARACTERIZATION 203(2023).