Abstract To investigate the effect of grain morphology on the mechanical properties of polycrystalline Mg, two types of bulk Mg samples with equiaxed and microlaminated grain structures were fabricated by spark plasma sintering (SPS) of as-received Mg powder and cryomilled disc-shaped Mg powder particles, respectively. Based on a detailed microstructural investigation, the mechanisms by which microstructure evolves and texture development occurs were identified and are discussed. The basal fiber textures in the SPS consolidated samples allow the plastic anisotropy in such textured Mg to be investigated. Compression tests at room temperature parallel and perpendicular to the SPS compaction axis determined that, in comparison to the conventional anisotropy observed in the equiaxed sample, the anisotropy of yield strength is reversed in the microlaminated sample, with the yield strength for c-axis extension being higher than that for c-axis contraction. The reversed compressive yield strength anisotropy observed in the sample that was cryomilled is related to the low twinning activity, limited twinning growth and the anisotropy induced by the microlaminated grain structure, which offers an opportunity to reduce or even reverse the intrinsic plastic anisotropy of hexagonal close packed Mg.

中文翻译：

---

具有微层压结构的镁的反向压缩屈服各向异性

摘要 为了研究晶粒形态对多晶 Mg 力学性能的影响，采用放电等离子烧结 (SPS) 对原样 Mg 粉和低温研磨的圆盘状 Mg 粉进行了制备，制备了两种具有等轴和微层状晶粒结构的块状 Mg 样品。粒子，分别。基于详细的微观结构研究，确定并讨论了微观结构演变和织构发展发生的机制。SPS 固结样品中的基础纤维织构允许研究这种织构 Mg 的塑性各向异性。在室温下平行和垂直于 SPS 压实轴的压缩测试确定，与在等轴样品中观察到的常规各向异性相比，在微层压样品中，屈服强度的各向异性是相反的，c 轴拉伸的屈服强度高于 c 轴收缩的屈服强度。在低温研磨样品中观察到的反向压缩屈服强度各向异性与低孪晶活性、有限的孪晶生长和由微层压晶粒结构引起的各向异性有关，这为减少甚至逆转六角密闭的固有塑性各向异性提供了机会。包装镁。