TY  - JOUR
AU  - Wang, Cui-ju
AU  - Zhang, Jin-Kai
AU  - Nie, Kai-bo
AU  - Xu, Chao
AU  - Deng, Kun-kun
PY  - 2025
TI  - The work hardening and softening behavior of spherical Tip/Mg-5Zn-0.3Ca composite
JO  - Journal of Magnesium and Alloys
SN  - 2213-9567
SP  - 2752
EP  - 2768
VL  - 13
IS  - 6
AB  - To obtain the Tip with different aspect ratios, the Tip/Mg-5Zn-0.3Ca composite prepared by semi-solid stir casting was subjected to extrusion at 220℃, 180℃, and 140℃, respectively. Then, the effect of the Tip’s aspect ratio on the microstructure, mechanical properties, work hardening and softening behaviors of Tip/Mg-5Zn-0.3Ca composites was investigated. The results indicated that the Tip could be elongated obviously after low-temperature extrusion, and the aspect ratio of which would reach to 13.7:1 as the extrusion temperature deceased to 140℃. Then the “Ti/Mg” layer-like structure was formed in the Tip/Mg-5Zn-0.3Ca composite. Accompanied with the elongation of Tip, the dynamic recrystallized grains and dynamic precipitates were both refined significantly, however, the dynamic recrystallization rate changed a little. The elongated Tip endowed the Tip/Mg-5Zn-0.3Ca composites with better matching of strength and toughness without the sacrifice of elongation and bending strain. Both the work hardening rate and softening rate of Tip/Mg-5Zn-0.3Ca composites increased with the increasing aspect ratio of Tip. The formation of “Ti/Mg” layer-like structure contributed to the redistribution of strain from large aggregations to a network-like distribution, which effectively suppresses the initiation and propagation of micro-cracks, thus enhancing the plasticity of the Tip/Mg-5Zn-0.3Ca composites.
UR  - https://doi.org/10.1016/j.jma.2024.06.028
DO  - 10.1016/j.jma.2024.06.028