ABSTRACT The present work reports the effect of Ta on densification and microstructure evolution during non-isothermal and spark plasma sintering of nanocrystalline W. Nanocrystalline W-5wt.%Ta alloy powder was synthesised using mechanical alloying. The nanocrystalline powder was characterised thoroughly using X-ray diffraction line profile analysis. Furthermore, the shrinkage behaviour of nanocrystalline powder was investigated during non-isothermal sintering using dilatometry. Subsequently, the alloy powder was consolidated using spark plasma sintering up to 1600°C. The role of Ta on stabilising the microstructure during spark plasma sintering of nanocrystalline W was investigated in detail using electron backscatter diffraction. The average grain size of spark plasma sintered W-5wt.%Ta alloy was observed as µm.

中文翻译：

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纳米晶W-5wt.%Ta合金放电等离子烧结过程中的显微组织演变和致密化

摘要 目前的工作报告了纳米晶 W 的非等温和放电等离子烧结过程中 Ta 对致密化和微观结构演变的影响。使用机械合金化合成了纳米晶 W-5wt.%Ta 合金粉末。使用 X 射线衍射线轮廓分析彻底表征纳米晶粉末。此外，使用膨胀计研究了非等温烧结过程中纳米晶粉末的收缩行为。随后，合金粉末使用高达 1600°C 的放电等离子烧结进行固结。使用电子背散射衍射详细研究了 Ta 在纳米晶 W 放电等离子体烧结过程中稳定微观结构的作用。放电等离子烧结的 W-5wt.%Ta 合金的平均晶粒尺寸为 µm。