Low temperature preparation of ZrC coatings on C/C composite via molten salt reaction
Zirconium carbide (ZrC) coatings were prepared on C/C composite via molten salt reaction process at relatively low temperatures of 800-1000℃.During the reaction process,potassium fluorozirconate (K2ZrF6) played a role transporting zirconium from the molten salt to the C/C composite surface.Elevating reaction temperature increased the growth rate of coatings,simultaneously leaded to rougher coatings.The coatings growth rate increased with reaction time at first and then dccreased gradually.The ZrC coatings prepared at 900℃ for 5h was ~2μm thickness.At the early stage,the low solubility of zirconium in the molten salt leaded to the low coatings growth rate.Secondly,the growth rate of the ZrC coatings was controlled by the chemical reaction between C/C composites and zirconium once zirconium was saturated in the molten salts.Thirdly,the control step of coatings formation turned into the diffusion of carbon through the formed ZrC coatings and which leaded to a gradual decrease of growth rate.
Zirconium carbide Coating C/C composite Molten salt reaction
Sian Chen Haifeng Hu Yudi Zhang Changrui Zhang Guangde Li
National Key Laboratory of Science and Technology on Advanced Ceramic Fibers and Composites,College of Aerospace and Materials Engineering, National University of Defense Technology,Changsha 410073, Hunan Province, China
国际会议
广州
英文
79-83
2012-11-16（万方平台首次上网日期，不代表论文的发表时间）