GH3230高温合金绿光飞秒激光的刻蚀特性  

Ablation Characteristics of GH3230 Superalloy Using Green Femtosecond Laser

作　　者：黄彩丽 蒋麒 蔺晓超[2] 杨诗瑞 郭鹏 崔梦雅 黄婷[1] Huang Caili;Jiang Qi;Lin Xiaochao;Yang Shirui;Guo Peng;Cui Mengya;Huang Ting(High-Power and Ultrafast Laser Manufacturing Lab,Faculty of Materials and Manufacturing,Beijing University of Technology,Beijing 100124,China;Beijing Power Machinery Research Institute,Beijing 100074,China)

机构地区：[1]北京工业大学材料与制造学部高功率及超快激光先进制造实验室,北京100124 [2]北京动力机械研究所,北京100074

出　　处：《中国激光》2023年第8期51-57,共7页Chinese Journal of Lasers

摘　　要：飞秒激光以其超窄脉宽和超高光强等特性被广泛应用于各种金属材料的加工。本课题组采用波长为515 nm的绿光飞秒激光器对GH3230镍基高温合金进行刻蚀试验,研究了GH3230高温合金的绿光飞秒激光刻蚀阈值、刻蚀率和极限刻蚀深度。结果表明:相比于红外飞秒激光,绿光飞秒激光的刻蚀阈值明显降低,刻蚀率显著提高;与红外飞秒激光刻蚀类似,随着刻蚀次数增加,刻蚀深度增大,但当刻蚀次数增加到一定值后,刻蚀深度出现饱和现象;激光能量密度越高,极限刻蚀深度越大;改变扫描策略进行双道刻蚀时,通过增加刻缝宽度可以增大刻蚀深度;激光诱导等离子体是影响刻蚀深度的主要因素。Objected Nickel-based superalloys exhibit high potential as raw materials for heated-end-core components because of their superior structural stability,oxidation resistance,corrosion resistance,fatigue resistance,and creep resistance.When compared to electrical discharge machining and normal pulsed laser machining,femtosecond laser machining offers higher precision and a lower heat effect.When a femtosecond laser pulse irradiates a metallic surface,electrons absorb photons and reach high temperature while the lattice remains unchanged,resulting in a low thermal effect.So,the femtosecond laser is expected to have the potential for machining GH3230 superalloys.At present,some reports have focused on femtosecond laser drilling technology and the increase of hole depth of nickel-based alloys,whereas femtosecond laser ablation technology and its characteristics on nickel-based alloys are yet to be discussed.In this study,a green femtosecond laser with a wavelength of 515 nm was used to investigate the ablation threshold,ablation rate,and ablation depth of a GH3230 nickel-based superalloy.Furthermore,an increase in the scanning width is proposed to expand the ablation depth.The effect of plasma induced by a femtosecond laser on the ablation depth is analyzed.Methods An as-forged GH3230 superalloy with a thickness of 1.2 mm was used as the base metal in laser ablation.First,a green femtosecond laser with a wavelength of 515 nm was used to ablate the GH3230 surface.The ablation width was measured using a white-light interferometer.The ablation thresholds at different scanning speeds were calculated by fitting the relationship curve between ablation width and laser fluence.The multi-pulse threshold incubation coefficient of GH3230 and ablation threshold of GH3230 under a single laser pulse were obtained by fitting the relationship curve between the ablation threshold and equivalent pulse number.The absorption spectrum of GH3230 was obtained using a spectrophotometer.After various scanning times ranging from 800 to 20000,t

关 键 词：激光技术 镍基高温合金 飞秒激光加工 刻蚀阈值 刻蚀深度 刻蚀率 

分 类 号：TG48[金属学及工艺—焊接]