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洞察用Al0.5CoCrFeNiTi0.5粘合剂对WC水泥碳化物的谷物精炼机制
Fengming Qiang1, Pengfei Zheng1, Pan He1,2
1School of Metallurgical Engineering, National and Local Joint Engineering Research Center for Functional Materials Processing, Xi'an University of Architecture and Technology, Xi'an 710055, China.
Materials (Basel, Switzerland)
|September 14, 2024
概括
高合金 (HEA) 通过形成新的M(Co,Fe,Ni) 3W3C相,有效地在化碳化物中提炼碳化物 (WC) 颗粒. 这种HEA粘合剂抑制了谷物生长,导致200nm以下的WC谷物以提高性能.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是金工业的一个方面.
- 纳米技术纳米技术
背景情况:
- 高合金 (HEAs) 正在成为化碳化物的新型结合剂.
- 传统的 (Co) 结合剂在控制碳化 (WC) 颗粒生长方面存在局限性.
研究的目的:
- 为了研究Al0.5CoCrFeNiTi0.5 HEA粘合剂在WC水泥碳化物中的作用.
- 阐明在热压烧结 (HPS) 过程中WC和HEA粘合剂之间的反应机制.
- 了解WC/HEA水泥化碳化物中的谷物精炼机制.
主要方法:
- 使用热压烧结 (HPS) 制备WC/(17~25重量%) 的Al0.5CoCrFeNiTi0.5硬化碳化物.
- 在HPS过程中,分析WC和HEA结合剂之间的反应和扩散过程.
主要成果:
- 与传统的Co结合剂不同,Al0.5CoCrFeNiTi0.5 HEA结合剂有效地抑制了WC粒的生长.
- 由于WC中的W和C原子扩散到HEA结合剂中,形成了一个M(Co,Fe,Ni) 3W3C相.
- 通过HEA结合剂限制W和C原子的反扩散,防止它们重新沉到大型WC粒上.
- 达到平均WC颗粒大小低于200nm.
结论:
- 在HEA粘合剂提供了一个新的途径,以实现精细的WC颗粒在化碳化物.
- 该研究为设计稳定的WC/HEA水泥化碳化物提供了对谷物精炼机制的见解.
- 这项工作指导了HEA结合剂的应用,以提高化碳化物的性能.
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