纳米TiN强化钛合金微观组织及耐腐蚀性能研究  

Microstructure and Corrosion Resistance of Titanium Alloy Reinforced with Nano-TiN

作　　者：刘文荣 胡怡宁 陈思宇 王涛[2] LIU Wenrong;HU Yining;CHEN Siyu;WANG Tao(College of Information Engineering,Qingdao Institute of Technology,Shandong Qingdao 266300,China;College of Aeronautical Engineering,Civil Aviation University of China,Tianjin 300300,China)

机构地区：[1]青岛工学院信息工程学院,山东青岛266300 [2]中国民航大学航空工程学院,天津300300

出　　处：《表面技术》2025年第8期126-135,共10页Surface Technology

基　　金：国家自然科学基金(52172360);中央高校基本科研业务费项目(3122023PY09)。

摘　　要：目的 提高TC4钛合金的耐腐蚀性能。方法 采用激光定向能量沉积技术制备纳米TiN陶瓷颗粒增强TC4复合材料。将TC4和纳米TiN/TC4试样浸入3.5%(质量分数)Na Cl溶液中进行电化学实验,并分析评价其耐腐蚀性。通过X射线衍射仪与扫描电子显微镜对材料的物相结构、微观组织、腐蚀形貌以及元素分布进行分析。结果 TC4和纳米TiN/TC4涂层与基体的冶金结合良好,没有明显裂纹。纳米TiN的完全熔化促进了纳米TiN/TC4复合材料中块状、条状TiXN相的析出。随着N含量降低,析出的TiXN相尺寸减小。二次析出的TiXN提供了大量形核位点,促进了纳米TiN/TC4晶粒转变为等轴晶。当浸泡1h后,TC4合金和纳米TiN/TC4复合材料的腐蚀电流密度分别为35.665 nA/cm^(2)、14.819 nA/cm^(2),极化电阻分别为2 084Ω、2 696Ω。浸泡10 d后,TC4的腐蚀电流密度增大,而纳米TiN/TC4的腐蚀电流密度减小为4.458 nA/cm^(2),极化电阻增大为4253Ω。TC4合金和纳米TiN/TC4复合材料表面形成的钝化膜主要由TiO_(2)组成,析出的Ti_(X)N能够促进纳米TiN/TC4钝化膜的形成。结论 由于TiXN作为微阴极优先诱导复合材料进入钝化状态,纳米TiN/TC4复合材料的耐腐蚀性明显优于TC4。纳米TiN的加入能够有效提高TC4合金的耐腐蚀性。As the operating environments for TC4 alloy become increasingly extreme,corrosion damage caused by conditions such as acidity,alkalinity,high temperature,and cyclic loading is becoming more severe.To enhance the corrosion resistance of TC4 titanium alloy,a nano-TiN ceramic particle reinforced TC4 composite was fabricated using laser directed energy deposition technology on a TC4 substrate.The process parameters are as follows:laser power of 2100 W,scanning speed of 20 mm/s,powder feed rate of 23.326 g/min,spot diameter of 3.8 mm,and overlap rate of 55%.The powder ratio is 10 wt.%nano-TiN and 90wt.%TC4 powder.The TC4 and nano-TiN/TC4 samples were immersed in a 3.5wt.%NaCl solution for 1 hour for electrochemical experiments to analyze and evaluate their corrosion resistance.The phase structure,microstructure,corrosion morphology,and elemental distribution of the materials were analyzed with an X-ray diffractometer and a scanning electron microscope equipped with energy-dispersive spectroscopy,providing comprehensive insights into their properties and performance.The results indicate that after adding nano-TiN,the nano-TiN/TC4 composite exhibits multiple low-intensity TiN diffraction peaks.Due to the formation of interstitial solid solution of Ti and N atoms in the TC4 matrix,the interplanar spacing of the nano-TiN/TC4 composite increases,causing the diffraction peaks to shift to the left.From a macroscopic perspective,the TC4 and nano-TiN/TC4 coatings exhibit excellent metallurgical bonding with the substrate,without obvious cracks.Nano-TiN absorbs more laser energy,resulting in a higher dilution rate of the nano-TiN/TC4 coating and an increased deposition layer thickness.In the microstructure of nano-TiN/TC4,the complete melting of nano-TiN promoted the precipitation of blocky and strip-like Ti_(X)N phases within the nano-TiN/TC4 composite.The N content in blocky Ti_(X)N phases is higher than that in strip-like Ti_(X)N phases,indicating that as the N content decreases,the size of the precipitated Ti_(X)N phases de

关 键 词：激光定向能量沉积 电化学腐蚀 纳米TiN TC4合金 微观组织 腐蚀行为 

分 类 号：TG146[一般工业技术—材料科学与工程]