TA15钛合金超薄中空四层结构超塑成形/扩散连接一体化成形及精度控制  

TA15 Titanium Alloy Superplastic Forming/Diffusion Bonding of Ultra-Thin Hollow Four-Layer Structure for Integrated Forming and Precision Control

作　　者：张晋源 秦立东 刘太盈 蒋少松[1,4] 彭鹏 李阳 ZHANG Jinyuan;QIN Lidong;LIU Taiying;JIANG Shaosong;PENG Peng;LI Yang(State Key Laboratory of Metal Precision Hot Processing,Harbin Institute of Technology,Harbin 150001,China;Capital Aerospace Machinery Corporation Limited,Beijing 100076,China;Beijing Xinghang Electro-Mechanical Equipment Co.,Ltd.,Beijing 100074,China;Harbin Hangyu Jingchuang Technology Co.,Ltd.,Harbin 150010,China)

机构地区：[1]哈尔滨工业大学金属精密热加工国家级重点实验室,哈尔滨150001 [2]首都航天机械有限公司,北京100076 [3]北京星航机电装备有限公司,北京100074 [4]哈尔滨宇航精创科技有限公司,哈尔滨150010

出　　处：《航空制造技术》2023年第9期75-84,共10页Aeronautical Manufacturing Technology

摘　　要：本文采用TA15钛合金热轧薄板作为原材料,探究超薄中空四层结构的超塑成形/扩散连接工艺。首先通过高温拉伸试验对TA15钛合金的超塑变形行为进行研究,获得了超塑成形过程的应力–应变曲线。然后通过有限元软件对薄壁横向局部贯通四层纵筋结构的超塑成形过程进行模拟,对成形过程中壁厚减薄、应力分布等行为进行研究,为后续超塑成形/扩散连接试验提供有效指导。最终成功制备了芯板直立筋良好、三角区宽度仅0.9 mm的超薄中空四层结构,其中面板最大减薄率为18.6%,芯板最大减薄率为55.1%,芯板与面板之间扩散连接区域的焊合率为92.1%~98.5%。TA15钛合金板材的原始显微组织晶粒细小破碎且呈等轴状,平均晶粒尺寸小于5μm,经长时间的超塑变形与热暴露后晶粒显著长大。The SPF/DB process of ultra-thin hollow four-layer structure was investigated by using TA15 titanium alloy hot rolled sheet.Firstly,the superplastic deformation behavior of TA15 titanium alloy in the process temperature range was studied by tensile test,and the corresponding stress–strain curves were obtained.Then,finite element software was used to simulate the design of the four-layer longitudinal reinforcement structure with thin-walled transverse local penetration,and the distribution of wall thickness reduction and stress concentration during the forming process is determined,which provides effective guidance for the subsequent diffusion bonding test.Finally,an ultra-thin hollow four-layer structure with good vertical ribs and a triangular zone width of only 0.9 mm was successfully prepared.The maximum thinning rate of the panel was 18.6%,the maximum thinning rate of the core plate was 55.1%,and the bonding rate of the diffusion bonding area between the core plate and the panel was 92.1%–98.5%.The original microstructure of TA15 sheet for forming is fine,broken and equiaxed,the average grain size is less than 5μm.After long-term superplastic deformation and thermal exposure,the grain size grows significantly.

关 键 词：TA15钛合金 超薄中空四层结构 超塑成形/扩散连接(SPF/DB) 显微组织 减薄率 应力分布 

分 类 号：V261[航空宇航科学与技术—航空宇航制造工程]