主动热防护结构光纤激光焊接侧吹保护试验研究  

Experimental Study on Side-Blow Protection of Active Thermal Protection Structure by Fiber Laser Welding

作　　者：袁振飞 蒋劲[1] 杜欣 程智伟 祁百鑫 武强 杨顺华[1] Yuan Zhenfei;Jiang Jin;Du Xin;Cheng Zhiwei;Qi Baixin;Wu Qiang;Yang Shunhua(Science and Technology on Scramjet Laboratory,CARDC,Mianyang621000,Sichuan,China;High-Power and Ultrafast Laser Manufacturing Laboratory,Faculty of Materials and Manufacturing,Beijing University of Technology,Beijing100124,China)

机构地区：[1]中国空气动力研究与发展中心高超声速冲压发动机技术重点实验室,四川绵阳621000 [2]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

出　　处：《应用激光》2023年第5期49-57,共9页Applied Laser

基　　金：国家自然科学基金面上项目(51775009);高超声速冲压发动机技术重点实验室开放课题(STSMY-KFKT-2020003)。

摘　　要：主动热防护构件作为航空航天领域的重要结构,光纤激光焊接是该类结构的优选制造工艺。苛刻的服役环境对焊缝成形、表面保护及气孔缺陷提出了很高的综合要求。基于侧吹保护的光纤激光非穿透深熔焊接工艺试验,采用超景深显微镜、数字RT检测及灰度处理等设备及方法,系统分析光气间距、气体输送角度、保护气输出长度及气体流量等参数对焊缝成形、焊缝保护效果及气孔的影响规律。结果表明,保护气流量及光气间距对焊缝形貌及气孔率影响较大,正值光气间距参数下焊缝气孔率较低,气孔率同保护气流量正相关。基于优化的气体保护参数,优化了喷嘴结构,实现了主动热防护凹槽三维构件的激光焊接制造,并通过台架测试。Active thermal protection component is an important structure in the field of aerospace.Fiber laser welding is the preferred manufacturing technique for this kind of structure.Stringent service environment puts forward higher comprehensive requirements for weld forming,surface protection,and porosity defects.Based on the side protective fiber non-penetrate deep penetration laser welding process test,the effects of phosgene spacing,gas transmission angle,protective gas output length and gas flow rate on weld formation,and weld protection and porosity were systematically analyzed by means of ultra-depth of field microscope,digital RT detection,and gray scale processing.The results show that the shielding gas flow rate and distance between the laser and the protective gas have a great influence on the weld morphology and porosity.Under the condition of positive distance between the laser and the protective gas,the weld porosity is low,and the porosity is positively correlated with the shielding gas flow rate.Based on the optimized gas protection parameters,the nozzle structure was optimized,and the 3Dcomponent of active thermal protection groove was manufactured by laser welding,which passed the bench test.

关 键 词：光纤激光 主动热防护结构 侧吹保护 焊缝形貌 气孔缺欠 

分 类 号：TG442[金属学及工艺—焊接]