不同热处理工艺下增材制造TC17钛合金组织与摩擦学性能研究  

Microstructure and Tribological Properties of Additively Manufactured TC17 Titanium Alloy Under Different Heat Treatment Processes

作　　者：王浩 胡怡宁 王涛[2] Wang Hao;Hu Yining;Wang Tao(Engineering Techniques Training Center,Civil Aviation University of China,Tianjin 300300,China;College of Aeronautical Engineering,Civil Aviation University of China,Tianjin 300300,China)

机构地区：[1]中国民航大学工程技术训练中心,天津300300 [2]中国民航大学航空工程学院,天津300300

出　　处：《中国激光》2024年第12期127-138,共12页Chinese Journal of Lasers

基　　金：国家自然科学基金(U2133202);四川省重大科技专项项目(2021ZDZX0001);研究生科技创新基金(2022YJS058)。

摘　　要：研究了不同热处理工艺对定向能量沉积TC17钛合金微观组织与摩擦学性能的影响,分析了热处理过程中的组织演变规律与20 N干滑动磨损下的综合磨损行为。结果表明,在退火与退火后固溶处理阶段,合金主要由初生α相及连续或不连续的晶界α相、β相组成,无相析出区伴随连续晶界α相存在。在退火后固溶处理的基础上进一步进行时效处理,针状次生α相开始析出,且随着时效温度的升高,初生与次生α相开始生长、粗化,无相析出区先消失后出现。硬度与磨损测试结果表明,经580℃时效处理后显微硬度最高(486.93 HV),此时有较强的弥散强化效果,摩擦学性能最优,磨损率仅为0.0451 mg/m。热处理后多种磨损机制混合存在,磨损率、磨损形貌取决于微观结构与氧化层的变化。研究结果为优化TC17合金摩擦学性能与热处理工艺提供了参考。Objective The TC17 alloy has excellent mechanical strength,fracture toughness,and corrosion resistance and is primarily used in the manufacturing of aero engine disk components.Directed energy deposition(DED)can achieve specific location repairs of damaged parts and 3D printing of complex and large parts.DED of TC17 alloy has been successfully applied to such parts as integral blade disks.However,the low hardness and poor wear resistance of TC17 alloy make it susceptible to fatigue fracture under the harsh use environment of aero engines,which limits its application in the aerospace field.At present,the problems of poor bonding strength,introduction of new defects,and inability to meet various performance requirements in the spraying of hard coatings on titanium alloy surfaces present potential risks and limitations in aerospace applications.Optimized heat treatment has unique advantages in solving these problems.Optimized heat treatment can adjust material properties by adjusting the microstructure.Several studies have been conducted on improving the tensile properties of TC17 by optimizing the heat treatment process,but further research is needed on whether optimized heat treatments can improve the wear resistance of deposited TC17 alloy.Therefore,in this study,the effects of annealing,post-annealing solid solution,and post-annealing solid solution aging treatments on the microstructure,hardness,and tribological properties of deposited TC17 alloy are investigated.The evolution of the structure during heat treatment and the comprehensive wear behavior under 20 N dry sliding wear are analyzed.The results provide a reference for optimizing the tribological properties and heat treatment process of TC17 alloy.Methods The experimental material is TC17 spherical powder,with an average particle size of 66.6μm(Fig.1).The experiment uses the semiconductor laser to generate lasers,and the robot,equipped with coaxial powder feeding,deposits the TC17 powder on the polished TC4 substrate in the argon environment(Fig.2).The

关 键 词：激光技术 钛合金 摩擦学性能 微观组织 热处理 定向能量沉积 

分 类 号：TG146.23[一般工业技术—材料科学与工程]