(1. 江西理工大學(xué) 材料科學(xué)與工程學(xué)院，贛州 341000；
2. 鎢資源高效開(kāi)發(fā)及應(yīng)用技術(shù)教育部工程研究中心，贛州 341000；
3. 北京科技大學(xué) 材料科學(xué)與工程學(xué)院，北京 100083)
摘 要: 采用等離子束表面冶金技術(shù)，通過(guò)多道搭接方式在低碳鋼基體上制備大面積鐵基復(fù)合超厚涂層。基于大面積涂層成形的特點(diǎn)，探討搭接率與涂層厚度等的變化規(guī)律，并利用掃描電鏡、X射線(xiàn)衍射儀、金相顯微鏡、顯微硬度計(jì)及磨損試驗(yàn)分析測(cè)試了涂層的相組成、組織及性能。結(jié)果表明：表面冶金涂層厚度可達(dá)3.0 mm，無(wú)裂紋、氣孔等缺陷；組織為γ-(Fe, Ni)枝晶、M23C6、CrB及原位合成的TiC陶瓷顆粒，與基體呈良好的冶金結(jié)合。由于顆粒強(qiáng)化、細(xì)晶強(qiáng)化和彌散強(qiáng)化等多種強(qiáng)化作用，大面積Fe基超厚涂層具有良好的耐磨性能。
關(guān)鍵字: 等離子束表面冶金；大面積涂層；成形；組織
（1. School of Materials Science and Engineering, Jiangxi University of Science and Technology,
Ganzhou 341000, China;
2. Engineering Research Center of High-efficiency Development and Application Technology of Tungsten Resources,
Ministry of Education, Ganzhou 341000, China;
3. School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China）
Abstract:By plasma jet surface metallurgy technology, Fe-based large area coating was produced on the low carbon steel through multiple channel overlap method. Based on the characteristic of the formation mechanism, the variation rules of overlapping rate and coating thickness were investigated. The phase compositions, microstructures and performance of the coatings were analyzed by scanning electron microscope, X-ray diffractometer, optical microscope, microhardness tester and wear tester. The results show that excellent bonding between the coating and carbon steel substrate is ensured by the strong metallurgical interface, and the coating is uniform, continuous and almost defect-free, 3 mm in thickness. The microstructure of the coating is mainly composed of γ-(Fe,Ni) dendrite, M23C6, CrB and TiC ceramic particle which is synthesized in-situ. Because of the particulate reinforced, dispersion strengthening and refinement strengthening, the microhardness and wear resistant of Fe-based coating can be enhanced.
Key words: plasma jet surface metallurgy; large area coating; formation; microstructure
