超塑成形/扩散连接四层夹层结构鼓包机理分析  

Mechanism analysis for bump of SPF/DB four-sheet sandwich hollow structure

作　　者：刘胜京[1] 雷海龙[1] 陈福龙[1] 

机构地区：[1]北京航空制造工程研究所,北京100024

出　　处：《锻压技术》2014年第8期30-36,共7页Forging & Stamping Technology

基　　金：总装备部"十二五"国防预研项目(51318040322)

摘　　要：简述了超塑成形/扩散连接四层夹层结构的典型成形过程。分析表明,外层蒙皮三角区为强度弱区,易出现沟槽、三角区宽、扩散连接强度低及壁厚分布不均等成形缺陷。对三角区鼓包变形过程进行了力学解析及试验分析,揭示了鼓包产生的原因和机理。真空热处理时,液体汽化引起密封腔内气压增大是造成鼓包的根本原因。阐明了液体体积分数、三角区宽度及蒙皮壁厚等各种因素对鼓包初始塑性变形及继续变形的影响。最后给出了三角区鼓包的预防措施及建议。The typical forming process of SPF/DB four-sheet sandwich hollow structure was sketched. The analysis shows that the forming defects, such as rill-like folds, over-width, lower diffusion bonding strength and uneven wall thickness distribution, etc. , are prone to appear in the external layer skin triangle area which becomes weak strength zone. The causes and mechanism of bump were revealed via mechanical and experimental analysis for bump forming process of triangle area. Pressure increasing caused by liquid vaporization in the hermetically sealed cavity is the primary cause of bump. The effects of various factors, such as liquid volume proportion, triangle area width and wall thickness of skin, etc. , on initial plastic and continual deformation of bump were clarified. Finally the effective precautions and recommendations for bump of triangle area were given.

关 键 词：超塑成形 扩散连接 四层夹层结构 鼓包 三角区 强度弱区 

分 类 号：TG306[金属学及工艺—金属压力加工]