ABSTRACT In this paper, in-situ VN reinforced powder metallurgy high-speed steel was fabricated from water atomised powder via pressureless sintering. During sintering, N would replace C to react with V, resulting in the formation of in-situ VN phase. According to the first-principles calculations, the formation energy of VN was – 9.45 eV while that of VC was – 9.08 eV. The relative density of as-sintered samples reached up to 99%. Homogeneous microstructure and fine reinforced phases were obtained. Ultrafine VN phase (0.5 μm) was uniformly distributed in the matrix. As a result, the mechanical properties were improved. The optimal mechanical performance was obtained in the sample with 1.0 wt.% C addition. The hardness, bend strength and impact energy were 65 HRC, 3011 MPa and 18–22 J, respectively. Besides, the sintering window significantly increased from ∼10 to 30∼50°C.

中文翻译：

---

水雾化粉末无压烧结原位 VN 增强粉末冶金 M30 钢

摘要 在本文中，原位 VN 增强粉末冶金高速钢是由水雾化粉末通过无压烧结制成的。在烧结过程中，N 将取代 C 与 V 反应，导致原位 VN 相的形成。根据第一性原理计算，VN 的形成能为 – 9.45 eV，而 VC 的形成能为 – 9.08 eV。烧结态样品的相对密度高达 99%。获得了均匀的显微组织和细小的强化相。超细 VN 相 (0.5 μm) 均匀分布在基质中。结果，机械性能得到改善。在添加 1.0 wt.% C 的样品中获得了最佳机械性能。硬度、弯曲强度和冲击功分别为 65 HRC、3011 MPa 和 18-22 J。除了，