无保护层纳秒脉冲激光强化对DD5单晶合金耐磨性能的影响  

Effect of Nanosecond Pulse Laser without Coating on Wear Resistance of DD5 Single Crystal Alloy

作　　者：史增祥 党晓凤 罗思海[1] 郭嘉琛 梁晓晴 何卫锋[1] 周留成[1] SHI Zengxiang;DANG Xiaofeng;LUO Sihai;GUO Jiachen;LIANG Xiaoqing;HE Weifeng;ZHOU Liucheng(Aviation Plasma Dynamics Laboratory,Aeronautical Engineering College,Air Force Engineering University,Xi'an 710038,China)

机构地区：[1]空军工程大学航空工程学院航空等离子体动力学实验室,西安710038

出　　处：《表面技术》2024年第7期136-145,共10页Surface Technology

基　　金：国家重大科技专项(J2019-Ⅳ-0003-0070);陕西省自然科学基础研究计划(2023-JC-QN-0402)。

摘　　要：目的提高发动机涡轮叶片榫头材料DD5单晶高温合金的高温耐磨性能。方法采用不同能量的无保护层纳秒脉冲激光对DD5单晶合金试样表面进行处理,利用摩擦磨损试验机获得DD5单晶合金在650℃下的摩擦磨损性能参数,并通过显微硬度计、扫描电子显微镜、能谱仪、共聚焦三维表面轮廓仪对磨损前后的DD5单晶试件进行表征分析,揭示纳秒脉冲激光强化技术提高单晶高温合金耐磨性能的机理。结果采用纳秒脉冲激光处理DD5单晶高温合金后,材料表层发生了重熔现象,并在重熔层中生成了弥散分布的铝的氧化物颗粒,其粒径为5~50nm;纳秒脉冲激光处理后产生的弥散分布的氧化铝颗粒为硬质相,它提升了单晶表面的显微硬度;经纳秒脉冲激光处理后,试样的磨损率降低了19.7%~37.6%,单晶合金的磨损机制以磨粒磨损为主。结论经纳秒脉冲激光处理后,单晶表面生成了含有弥散分布的纳米氧化铝颗粒的重熔层,在它与激光诱导的等离子体冲击波产生的硬化层的共同作用下,提升了镍基单晶高温合金在高温下的耐磨性能。Nickel-based single crystal superalloys are widely used in advanced aero-engine turbine blades due to their excellent high temperature performance.However,the blade tenon is prone to wear failure due to the combined action of friction and alternating load during service.Nanosecond pulse laser shock peening without coating is an advanced laser surface modification technology,which improves the service performance of materials by improving the surface gradient structure of materials.The work aims to study the effect of nanosecond pulsed laser shock peening without coating on the wear resistance of nickel-based single crystal superalloy DD5 at high temperature(650℃).The nickel-based single crystal superalloy DD5 was cut into long squares of 30 mm×10 mm×3 mm under the(100)/[001]orientation condition and polished to 2000#with sandpaper until the surface roughness(Ra)of the material was less than 0.2μm.Then,the sample was ultrasonically cleaned in alcohol for 30 min and dried.The YSM2000-C30A laser was used to treat the sample.The spatial energy was Gaussian distribution,the wavelength was 532 nm,the pulse width was 8-10 ns,and the spot diameter was 0.4 mm.The path of laser treatment was'S'shape,the frequency was 500 Hz,and the overlap rate was 50%.The samples were treated with laser energy of 50,80,and 120 mJ,respectively,and water was used as the constraint layer.Then,the microstructure of the surface layer of single crystal superalloy DD5 was observed by ultra-depth-of-field optical microscope(Keyence,KH-8700,Japan)and scanning electron microscope(Zeiss,Segma 300,Germany).The element analysis of nickel-based single crystal superalloy was carried out by energy spectrometer.The surface profile and roughness of the material were analyzed by open source software Gwyddion 2.58,and the microhardness of the surface and cross section of the material were tested by microhardness tester(Huayin,HV-1000A,China).The friction test was carried out on a multifunctional friction and wear tester(Retec,MFT-5000,America).The volum

关 键 词：镍基单晶高温合金 纳秒脉冲激光 氧化铝颗粒 显微硬度 摩擦磨损 磨损机制 

分 类 号：TG665[金属学及工艺—金属切削加工及机床] TG132.3[一般工业技术—材料科学与工程]