微/纳结构Cr_(3)C_(2)-NiCr陶瓷涂层在3.5%NaCl溶液中的腐蚀磨损行为  

Corrosion Wear Properties of Micro/nano-structured Cr_(3)C_(2)-NiCr Ceramic Coatings in 3.5wt.%NaCl Solution

作　　者：南鹏娟 贾均红 焦小雨 张宗宇 徐艺飞 张庆庆 NAN Pengjuan;JIA Junhong;JIAO Xiaoyu;ZHANG Zongyu;XU Yifei;ZHANG Qingqing(Shaanxi University of Science&Technology,Xi'an 710021,China)

机构地区：[1]陕西科技大学,西安710021

出　　处：《表面技术》2025年第1期150-160,共11页Surface Technology

基　　金：国家自然科学基金(52175178)。

摘　　要：目的设计并制备微/纳结构Cr_(3)C_(2)-NiCr陶瓷涂层,以改善机械部件的耐腐蚀磨损性能。方法采用行星式球磨机结合喷雾造粒仪制备了微/纳结构Cr_(3)C_(2)粉体,造粒得到的Cr_(3)C_(2)粉体与NiCr粉混合均匀后通过等离子喷涂技术,在316L不锈钢基体上制备了微/纳结构Cr_(3)C_(2)-NiCr复合涂层。利用球-盘式往复摩擦磨损试验机结合电化学工作站,研究了3.5%NaCl水溶液中复合涂层的腐蚀磨损性能。利用扫描电镜观察了复合粉体、复合涂层和复合涂层腐蚀磨损后的微观形貌,利用X射线衍射仪分析了复合粉体和复合涂层的相变。结果复合粉体表面大小颗粒随机分布,表面结构致密。4种复合涂层显微结构致密,未见明显孔隙及裂纹生成。WNC3(纳米Cr_(3)C_(2)含量)复合涂层的孔隙率低至0.7%,显微硬度为853.26HV0.3。WNC3涂层所遭受的腐蚀程度最小。复合涂层动态下的自腐蚀电流密度相较于静态下有所升高,磨损和腐蚀的共同作用导致滑动接触下涂层的腐蚀速率大于静态下的涂层腐蚀速率。WNC3复合涂层的平均摩擦因数(约0.20)和磨损率(约9.7×10^(‒7)mm^(3)/(N·m))均最低。在摩擦过程中,磨损痕迹内部的腐蚀电流密度较高,腐蚀溶液通过涂层的缺陷不断向涂层内部扩散,导致局部剥落面积扩大。结论添加50%纳米Cr_(3)C_(2)晶粒使涂层内部更加致密,涂层孔隙率降低,显微硬度增加,在3.5%NaCl水溶液中表现出优异的耐腐蚀磨损性能。复合涂层在3.5%NaCl水溶液中腐蚀磨损时,腐蚀会降低复合涂层的机械性能,增加复合涂层的磨损;而磨损会导致复合涂层暴露出更多的缺陷,进而增加腐蚀发生的可能。In order to improve the corrosion and wear resistance of mechanical parts,a micro/nano-structured Cr_(3)C_(2)-NiCr ceramic coating was designed and prepared.The Micro/nano-structured Cr_(3)C_(2)powder was prepared using a planetary ball mill combined with a spray granulator.The Cr_(3)C_(2)powder and NiCr powder were uniformly mixed,and the micro/nanostructured Cr_(3)C_(2)-NiCr composite coating was prepared on 316L stainless steel by plasma spraying.The corrosion and wear properties of the composite coatings in 3.5wt.%NaCl aqueous solution were investigated by ball-disc reciprocating friction and wear tester combined with an electrochemical workstation.The surface size particles of the composite powder were randomly distributed and the surface structure was compact.The microstructure of the four composite coatings was compact and no obvious pores and cracks were found.The porosity of the WNC3(nano-Cr_(3)C_(2)content)composite coating was as low as 0.7%,and the microhardness was 853.26HV0.3.The corrosion degree of the WNC3 coating was the lowest.The average friction coefficient(0.20)and wear rate(9.7×10^(‒7)mm^(3)/(N·m))of the WNC3 composite coating were the lowest.In conclusion,the addition of 50%nano-Cr_(3)C_(2)grains can make the interior of the coating more compact,and reduce the porosity and increase the microhardness of the coating.The coating shows excellent corrosion and wear resistance in 3.5wt.%NaCl aqueous solution.Corrosion of the composite coating in 3.5wt.%NaCl aqueous solution will reduce the mechanical properties of the composite coating and increase the wear of the composite coating,while the wear will lead to more defects in the composite coating and increase the possibility of corrosion.

关 键 词：微/纳结构 复合涂层 Cr_(3)C_(2)-NiCr陶瓷涂层 等离子喷涂 腐蚀磨损 

分 类 号：TG174[金属学及工艺—金属表面处理]