The mechanism on the formation and evolution of heterogeneous bimodal microstructure of die-cast AM60B alloy constructed by isothermal upsetting deformation
Source abstract
Abstract
In this paper, isothermal upsetting experiments were conducted at temperatures ranging from 300°C to 400°C with a constant deformation of 25% to investigate the influence of temperature on the microstructure evolution, deformation mechanisms, and mechanical properties of a die-cast AM60B alloy. The results indicates that the deformation temperature is an important factor to affect the formation of heterogeneous bimodal microstructure, which is more easily formed at high temperatures. It exhibits a unimodal microstructure consisting of coarse grains deformed at 300°C, and there have developed heterogeneous bimodal microstructures comprising fine dynamic recrystallized (DRX) grains and coarse deformed grains at 350°C and 400°C. Among them, the heterogeneous bimodal microstructure of the specimen is caused by particle-stimulated nucleation (PSN) and continuous dynamic recrystallization (CDRX) at 350°C. However, when the temperature rises to 400°C, the heterogeneous bimodal microstructure is mainly formed by CDRX and discontinuous dynamic recrystallization (DDRX), accompanied by limited PSN. In addition, fine particles Mg 17 Al 12 precipitated at 350°C promote DRX through PSN mechanism, while linear Mg 17 Al 12 precipitated along DRX grain boundaries at 400°C, providing new nucleation sites for DRX region expansion. These precipitated phases further lead to the formation of heterogeneous bimodal microstructure by promoting DRX nucleation. Excellent comprehensive mechanical properties are achieved in the alloy, owing to the heterogeneous bimodal microstructure that brings about multiple improvements: improvement of DRX ratio, grains refinement, reduction of dislocation density and texture weakening.
Source: openalex_inverted_index · Quality: baseline
Research context
OpenAlex topics: Magnesium Alloys: Properties and Applications · Aluminum Alloy Microstructure Properties · Microstructure and mechanical properties
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (54)
Show source-provided references
1. Advances in high-strength and high-thermal conductivity cast magnesium alloys: strategies for property optimization10.1016/j.jallcom.2025.180843 ↗
2. Effect of heat treatment on microstructure evolution and mechanical properties of selective laser melted Mg-11Gd-2Zn-0.4Zr alloy10.1016/j.msea.2021.142139 ↗
3. Recent research and advances in extrusion forming of magnesium alloys: a review10.1016/j.jallcom.2023.170080 ↗
4. Evolution, limitations, advantages, and future challenges of magnesium alloys as materials for aerospace applications10.1016/j.jallcom.2024.176707 ↗
5. Synergism in pre-upsetting on grain refinement and basal texture weakening of AZ31 Mg alloy by continuous variable cross-section direct extrusion10.1016/j.jallcom.2024.175889 ↗
6. Enhanced strength-ductility synergy in a Ta-doped CoCrNi medium-entropy alloy with a dual heterogeneous structure10.1016/j.msea.2022.144293 ↗
7. Enhancing strength-ductility synergy in heterostructured magnesium alloys by tailoring heterogeneity levels10.1016/j.msea.2025.147906 ↗
8. Optimization in strength-ductility of soft plate rolled AZ31 magnesium alloy via CDRX and shear band-induced DRX10.1016/j.jallcom.2025.181303 ↗
9. A novel strategy synergistically enhances the strength and ductility of Mg-Gd-Zr alloys by tailoring a heterogeneous structure10.1016/j.jallcom.2025.179782 ↗
10. Multi scale performance breakthrough of Sc/Zr/Mn microalloying controlled wire arc additive manufacturing of high-strength light alloys10.1080/17452759.2025.2567397 ↗
11. Effect of dynamic recrystallization, LPSO phase, and grain boundary segregation on heterogeneous bimodal microstructure in Mg-9.8Gd-3.5Y-2.0Zn-0.4Zr alloy10.1016/j.jmrt.2023.08.180 ↗
12. A fully recrystallized heterogeneous grain structure with dispersed second phases for enhancing strength-ductility synergy in an Al-Cu-Mn alloy10.1016/j.jallcom.2024.175989 ↗
13. Simultaneous improvement of strength and ductility in ZK60 magnesium alloy by constructing the bimodal grain structure10.1016/j.jmrt.2022.12.002 ↗
14. Achieving strength-ductility synergy of Mg-Al-Ca-Zn alloy with a lamellar heterogeneous structure10.1016/j.jmrt.2025.03.277 ↗
15. Hybrid additive manufacturing of ceramic/aluminum-titanium gradient composites via arc and laser cladding eutectic pools10.1080/17452759.2024.2419950 ↗
16. The synergy effect of fine and coarse grains on enhanced ductility of bimodal-structured Mg alloys10.1016/j.jallcom.2018.11.229 ↗
17. Strong and ductile AZ31 Mg alloy with a layered bimodal structure
18. A superplastic bimodal grain-structured Mg-9Al-1Zn alloy processed by short-process hard-plate rolling10.1016/j.mtla.2019.100443 ↗
19. Mechanical properties and deformation mechanism of Mg-Al-Zn alloy with gradient microstructure in grain size and orientation10.1016/j.msea.2017.04.005 ↗
20. The role of bimodal-grained structure in strengthening tensile strength and decreasing yield asymmetry of Mg-Gd-Zn-Zr alloys10.1016/j.msea.2017.09.125 ↗
21. Ultra high-strength Mg-Gd-Y-Zn-Zr alloy sheets processed by large-strain hot rolling and ageing10.1016/j.msea.2012.03.087 ↗
22. Achieving bimodal microstructure and enhanced tensile properties of Mg–9Al–1Zn alloy by tailoring deformation temperature during hard plate rolling (HPR)10.1016/j.jallcom.2018.04.328 ↗
23. Fabrication of extraordinary high-strength magnesium alloy by hot extrusion10.1016/j.scriptamat.2009.06.003 ↗
24. Heterogeneous bimodal microstructure and its formation mechanism of Mg-Gd-Y-Zn-Zr alloy during isothermal compression10.1016/j.jallcom.2023.169523 ↗
25. Controlling dynamic recrystallization via modified LPSO phase morphology and distribution in Mg-Gd-Y-Zn-Zr alloy10.1016/j.jma.2023.01.006 ↗
26. Achieving an ultra-high strength and moderate ductility in Mg-Gd-Y-Zn-Zr alloy via a decreased-temperature multi-directional forging10.1016/j.matchar.2020.110804 ↗
27. Microstructure and texture evolution of AZ31 mg alloy processed by multi-pass compressing under room temperature
28. Enhanced quasi-isotropic ductility in bi-textured AZ91 Mg alloy processed by up-scaled RD-ECAP processing10.1016/j.jallcom.2018.12.008 ↗
29. The microstructure evolution, texture weakening mechanism and mechanical properties of AZ80 Mg alloy processed by repetitive upsetting-extrusion with reduced deformation temperature10.1016/j.jallcom.2021.160871 ↗
30. Dynamic recrystallization behaviors of high Mg alloyed Al-Mg alloy during high strain rate rolling deformation10.1016/j.msea.2019.03.028 ↗
31. Influence of processing temperature on microhardness evolution, microstructure and superplastic behaviour in an Al–Mg alloy processed by high-pressure torsion10.1016/j.jmrt.2023.03.167 ↗
32. Grain refinement mechanism in gradient nanostructured Mg-Gd-Y-Zn-Zr alloy prepared by severe shear deformation10.1016/j.msea.2024.146207 ↗
33. Hot deformation of cast AZ31 and AZ80 magnesium alloys – influence of Al content on microstructure and texture development
34. Synergistic enhancement of thermal conductivity and mechanical properties in cast Mg-Zn-Zr-Sr alloys via grain refinement and solute redistribution10.1016/j.jallcom.2025.182094 ↗
35. Effect of RE/Zn atomic ratio on the microstructure of Mg-Zn-Gd-Y alloys during rolling process: a new composition design strategy for high-strength and high-thermal-conductivity magnesium alloy
36. Current progress in strengthening, plastic deformation and thermal stability of Mg alloys10.1016/j.jallcom.2025.179151 ↗
37. Investigation of lightweight wheel design using alloy materials through structural analysis10.1016/j.matpr.2023.01.013 ↗
38. Design and optimization of aluminium alloy wheel rim in automobile industry10.1016/j.matpr.2023.01.207 ↗
39. Deformation behaviour analysis of different offset rim under different loading using finite element method10.1016/j.matpr.2019.09.119 ↗
40. Rotating backward extrusion deformation induced dissolution and re-precipitation of second phases and microstructure gradient refinement in Mg-RE-Zn alloy10.1016/j.jallcom.2025.179997 ↗
41. Mg-Alloys for forging applications—A review10.3390/ma13040985 ↗
42. Predictive microstructure image generation using denoising diffusion probabilistic models10.1016/j.actamat.2023.119406 ↗
43. 5Zr alloy via multidirectional forging after analyzing its compression behavior10.1016/j.jmst.2020.08.054 ↗
44. Dynamic recrystallization behaviors of Mg-Gd-Y-Zn-Zr alloy with different morphologies and distributions of LPSO phases10.1016/j.msea.2017.12.103 ↗
45. Hot deformation behavior of Mg-5Li-3Al-2Zn-0.2Zr alloy based on constitutive analysis, processing map, and microstructure evolution10.1016/j.jallcom.2023.168983 ↗
46. Effective values of critical resolved shear stress for slip in polycrystalline magnesium and other hcp metals10.1016/j.scriptamat.2010.05.047 ↗
47. Deformation mechanism of Mg-Gd-Y-Zn-Zr alloy containing long-period stacking ordered phases during hot rolling10.1007/s11661-020-05667-7 ↗
48. The texture and its optimization in magnesium alloy10.1016/j.jmst.2019.10.010 ↗
49. Evolution of long-period stacking ordered phases and their effect on recrystallization in extruded Mg-Gd-Y-Zn-Zr alloy during annealing10.1016/j.matchar.2020.110515 ↗
50. Uncovering the role of dynamic recrystallization in <0001> texture formation during hot extrusion in Mg-Gd-Y-Zn alloy10.1016/j.jallcom.2025.180482 ↗
51. Efficient grain refinement of as-cast al-mg-si alloy via warm deformation: grain boundary based quantitative analysis on its dynamic recrystallization behaviors10.1016/j.matdes.2025.114273 ↗
52. Effect of temperature on the hot deformation behavior of AZ80 magnesium alloy10.1016/j.msea.2020.139923 ↗
53. The influence of heat-treatment on regulating the content and morphology of LPSO phase in Mg-Y-Al alloy and its strengthening mechanism at room temperature10.1016/j.jma.2025.02.020 ↗
54. Tensile properties and fracture mechanism of Al–Mg alloy subjected to equal channel angular pressing10.1016/j.msea.2007.01.062 ↗