With the miniaturization of the products such as micro springs and microneedles in micro-electromechanical systems (MEMS), improved plasticity of the metals is required. Microforming process are prospective to manufacture these microparts owing to its high productivity, the near-net-shape and good mechanical properties of the formed products. However, the metals such as titanium (Ti) and magnesium alloys with hexagonal close-packed (HCP) structure exhibit poor plasticity at room temperature due to the limited slip systems, resulting in the decrease of uniform elongation. In particular, the decreased uniform formability of the metal foils causes their faster fracture. Although forming at elevated temperatures is an effective approach to improve the plasticity of the foils, the strength of the material decreases, especially forming above recrystallization temperatures. This restricts the application of the products when bearing high strength is necessary.
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