Deformation behavior and microstructure evolution of rare earth magnesium alloy during rotary extrusion

Research Progress on Microstructure Evolution and Strengthening-Toughening Mechanism of Mg Alloys by Extrusion

“…With certain torsion process parameters, the torsion extrusion specimen shows gradient change. Yu et al [10] found that the flow stress (100 MPa) of the torsional extrusion Liu et al [9] confirmed that the mechanical properties of Mg-4Li alloy after four-pass ECAP were relatively stable and the grains were alternately elongated or spheroidized. The mechanical strength of Mg-4Li-3(AL-12Si)-1(Al-5Ti-1B) alloy reaches the peak value after two passes of ECAP (UTS, YS and elongation can reach 243 ± 2 MPa, 170 ± 2 MPa and 16.4 ± 0.4%).…”

“…The sum of the equivalent of torsion and indirect extrusion can be described using Equation (2) [ 29 ]: where N signifies the number of revolutions, h and h 0 represent the final and initial bottom thickness of the specimen, and R 0 and R 1 are the punch radius and the die inner radius. The shear stress (τ) and shear strain (γ) can be converted by torque-rotation, and the expression [ 10 , 30 ] is: where R corresponds to the punch radius, θ signifies the torsion angle, L describes the extrusion length, n stands for the strain hardening coefficient, and m signifies the strain rate sensitivity factor ( n = m = 0).…”

“…After indirect extrusion, the (0001) basal orientation coexisted with and textures. At the same time, Yu et al [ 10 ] found that the microhardness of Mg-11.95Gd-4.5Y-2Zn-0.37Zr (wt.%) alloy decreased with an increase in torsional revolutions, and the matrix and the second phase were more uniformly distributed. The grain refinement performance has a positive effect on the rotational speed and the DRX refinement is in dynamic competition with growth at a constant temperature and strain rate.…”

“…With the development of technology, many extrusion processes have been proposed and researched. Commonly used methods include direct extrusion, indirect extrusion [8], equal channel angular pressing [9] and rotary extrusion [10]. Among these different extrusion methods, there are attractive methods owing to their relatively simple procedures, Materials 2023, 16, 3791 2 of 20 reduced material handling and large deformations.…”

International trends analysis for subject of rare earth-magnesium alloys

“…Compared with the traditional magnesium alloy, rare earth-magnesium alloys not only retains the advantages of low density, high specific stiffness and strength, good electromagnetic shielding and damping and easy recycling but also improves the overall performance of magnesium alloy by adding rare earth elements, especially heat resistance and mechanical properties at room/high temperature. [1][2][3][4] In order to accurately obtain development status and potentials and draw a "topographical map" for the development trends, this paper focuses on the rare earth-magnesium alloys and analyzes international trends and subjects of related studies with literature database and a progressive plane-to-point framework based on the qualitative investigation and expert consultation. The purpose is to analyze domestic and foreign research status and technical hotspot of the field and further demonstrate China's research status in the field of rare earthmagnesium alloys.…”