Abstract Magnesium alloy Mg-4Y-3Nd (WN43) was subjected to ECAP at T∼300 °C up to 8 passes, using route BC. The initial as-extruded material with average grain size of ∼10 μm, was effectively refined down to sub-micrometer scale, reaching a grain size of ∼380 nm, after 8 passes. At the same time, secondary phase particle precipitation of β′-Mg12Nd2Y, and β-Mg14Nd2Y was induced. At 8 passes, fragmentation and coarsening of these phases occurred. Both grain refinement and β′/β precipitation strengthened the alloy. The strengthening was detected by nanoindentation hardness and accounted of up to 30% increment at 8 ECAP pass, compared to the initial extruded condition.

中文翻译：

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ECAP对Mg-Y-Nd（WN43）合金的二次相析出和热稳定组织细化

摘要 镁合金 Mg-4Y-3Nd (WN43) 在 T~300 °C 下进行 ECAP 最多 8 道次，使用路线 BC。平均晶粒尺寸约为 10 μm 的初始挤压材料被有效地细化到亚微米级，经过 8 道次后达到~380 nm 的晶粒尺寸。同时诱导了β'-Mg12Nd2Y和β-Mg14Nd2Y的二次相颗粒析出。在第 8 次通过时，这些相发生碎裂和粗化。晶粒细化和β'/β 析出均增强了合金。与初始挤压条件相比，通过纳米压痕硬度检测到强化，并且在第 8 次 ECAP 通过时增加了 30%。