摘要
【目的】总结纳米或超细碳化钨钴(WC-Co)粉体制备过程的研究,解决WC-Co做为热喷涂原料对机械零件的磨损和腐蚀的影响。【研究现状】总结纳米或超细WC-Co制备过程强化、反应路径,以及Co对还原碳化过程的作用等;其中机械作用力强化包括球磨强度的影响、氧化钨原料的影响、反应温度的影响,原子或分子水平强化包括气相化学合成、喷雾转化,气相碳质强化反应过程包括烃类物质、一氧化碳;纳米或超细WC-Co制备过程反应路径包括还原过程、碳化过程;对还原碳化过程的作用包括Co对氧化钨还原碳化过程具有催化作用、Co影响WC-Co产物粒径、Co含量增加降低碳化温度、Co促进气态碳源析碳等。【结论与展望】提出WC-Co粉体制备反应路径方面,应深入揭示制备反应路径,应进一步分析缺碳相η物相在制备过程中的作用,对W、Co、C扩散的影响机制;认为模拟分析反应过程中还原碳化气与固体原料之间的热量、质量传递过程,可为制备过程进一步优化调控和反应器放大设计奠定理论基础;同时WC-Co粉体热喷涂性能方面,用于机械件的喷涂处理时,应测试涂层的抗磨损和腐蚀性能,反馈调控优化和制备过程。
Significance Using nano or ultra-fine tungsten carbide cobalt(WC-Co)powder as thermal spray material can effectively solve the wear and corrosion problems in mechanical parts.This paper summarizes and analyzes the research progress on enhancing the preparation process of such powders.Progress Based on various enhancement methods and approaches,different preparation methods of nano or ultra-fine WC-Co powder are reviewed,and their reaction paths are analyzed.The role of cobalt(Co)in the preparation process of nano or ultrafine WC-Co powder is also discussed.Enhancement technologies for the preparation process mainly include mechanical force enhancement,atomic or molecular-level enhancement,and gas-phase carbon source enhancement.The reaction paths during the preparation process mainly involves two stages:reduction and carbonization.There are three paths:1)tungsten carbide(WC)andη-phase are formed during carbonization;2)tungsten trioxide(WO3)is first reduced to tungsten(W),then theη-phase is formed,followed by further carbonization to form WC-Co;3)the reduction and carbonization process occurs without the formation of theη-phase.During the preparation of nano or ultra-fine WC-Co powder,Co plays the roles of catalysis,promoting carbonization,reducing the carbonization temperature,and decreasing the particle size of the product.Conclusions and Prospects The preparation and application of nano or ultra-fine WC-Co powder can be further developed in the following areas.The mechanisms of the enhancement process in WC-Co powder preparation and the interaction mechanisms of Co-W-C should be further elucidated.The role of carbon-deficientη-phase in the preparation process remains unclear,and its impact on the diffusion mechanisms of W,Co,and C during preparation needs further analysis.By clarifying these mechanisms,the optimization of the preparation process can be guided,allowing for the control of the free carbon mass content within 0.2%,and the production of composite powder with particle sizes under 100 nm.Moreover,the heat and mass transfer laws during the reaction process should be further examined.Using fluid simulation software,the heat and mass transfer processes between carbonized gas and solid raw materials in the reaction process can be simulated and analyzed,providing a basis for studying the reaction process mechanisms,optimizing the preparation process,and designing scalable reactors.The thermal spraying properties of composite powders also need to be further studied.It is necessary to apply the ultra-fine WC-Co powder prepared by relevant technical routes to the surface treatment of mechanical parts,testing the wear and corrosion resistance of the resulting coating,and using this performance data to refine the preparation process.
作者
潘锋
尚慧俊
黎亨利
杜占
PAN Feng;SHANG Huijun;LI Hengli;DU Zhan(State Key Laboratory of Mesoscience and Engineering,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China;College of Materials Science and Engineering,Beijing University of Technology,Beijing 100124,China;School of Chemistry and Chemical Engineering,Shihezi University,Shihezi 832003,China;Chinalco Environmental Protection and Energy Conservation Group Co.,Ltd.,Xiong’an 050004,China)
出处
《中国粉体技术》
CAS
2025年第1期1-10,共10页
China Powder Science and Technology
基金
国家自然科学基金项目,编号:22078326、21878305。
