Abstract In this study, the authors successfully obtained high strain-rate superplasticity (HSRS) for an AZ91 Mg alloy using rapidly solidified flaky powder metallurgy (RS FP/M). The RS FP/M AZ91 shows an elongation to failure of 465% at a temperature and initial strain rate of 623 K and 10−2 s−1, respectively. Furthermore, the optimum superplastic strain rate for the maximum elongation was 10−2 s−1, which is higher than those attained by other methods. The HSRS obtained in this study is attributed to an effective grain refinement (∼1 μm) and high thermal stability. The bimodal grain structure may further contribute to HSRS.

中文翻译：

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AZ91合金快速凝固片状粉末冶金实现高应变率超塑性

摘要 在本研究中，作者使用快速凝固片状粉末冶金 (RS FP/M) 成功获得了 AZ91 镁合金的高应变率超塑性 (HSRS)。RS FP/M AZ91 在温度和初始应变速率分别为 623 K 和 10-2 s-1 时的断裂伸长率为 465%。此外，最大伸长率的最佳超塑性应变速率为 10-2 s-1，高于其他方法获得的超塑性应变速率。本研究中获得的 HSRS 归因于有效的晶粒细化（~1 μm）和高热稳定性。双峰晶粒结构可能进一步有助于 HSRS。