Abstract Two Mg alloys containing 0.03 at% and 0.18 at% Nd were designed to investigate the effects of solute concentration, and thermomechanical processing on the strengths of related deformation modes. Annealing treatments were conducted to stimulate grain coarsening for as-extruded alloys. In view of solute concentration effect, we conducted compressive tests and microstructure characterization to reveal and analyze the activities of the related deformation modes and their corresponding strengths. We find that the solute concentration of Nd does not affect the nucleation CRSS for {10-12} twinning. However, with the increase of Nd concentration, the nucleation CRSS for pyramidal -slip was greatly reduced. We also use a thermomechanical processing route, in terms of pre-compression, unloading, intermediate annealing, and re-compression, to explore the effect of solute segregation on strengths of related deformation modes. It is found that the CRSS for the migration of {10-12} twinning dislocation increased significantly after the intermediate annealing treatment for Mg-0.18Nd alloy. We conclude that when designing high ductility Mg alloys, from the perspective of reducing the strength discrepancies between soft deformation modes and hard deformation modes, important factors including the type of alloying element, solute concentration, and pre-deformation strain need to be taken into account.

中文翻译：

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设计具有高延展性的镁合金：减少软变形模式和硬变形模式之间的强度差异

摘要 设计了两种含 0.03 at% 和 0.18 at% Nd 的镁合金，以研究溶质浓度和热机械加工对相关变形模式强度的影响。进行退火处理以刺激挤压态合金的晶粒粗化。针对溶质浓度效应，我们进行了压缩试验和微观结构表征，以揭示和分析相关变形模式的活动及其相应的强度。我们发现 Nd 的溶质浓度不影响 {10-12} 孪晶的成核 CRSS。然而，随着Nd浓度的增加，锥体滑移的成核CRSS大大降低。我们还使用热机械加工路线，在预压缩、卸载、中间退火和再压缩方面，探讨溶质偏析对相关变形模式强度的影响。发现Mg-0.18Nd合金经过中间退火处理后，{10-12}孪晶位错迁移的CRSS显着增加。我们得出结论，在设计高延性镁合金时，从减少软变形模式和硬变形模式之间的强度差异的角度来看，需要考虑合金元素类型、溶质浓度和预变形应变等重要因素。 .