泡沫铝三明治预制坯变形失效及对发泡的影响  

Deformation Failure of Aluminium Foam Sandwich Precursor and Effects on Its Foaming Behavior

作　　者：王耀奇 任学平[2] 韩玉杰[1] 李红 侯红亮 Wang Yaoqi;Ren Xueping;Han Yujie;Li Hong;Hou Hongliang(Beijing Key Laboratory of Digital Plasticity Forming Technology and Equipment,Aeronautical Key Laboratory for Plastic Forming Technologies,AVIC Manufacturing Technology Institute,Beijing 100024,China;School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]中国航空制造技术研究院,塑性成形技术航空科技重点实验室,数字化塑性成形技术及装备北京市重点实验室,北京100024 [2]北京科技大学材料科学与工程学院,北京100083

出　　处：《稀有金属》2019年第10期1115-1120,共6页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(50875249)资助

摘　　要：利用粉末包套轧制法制备出泡沫铝三明治预制坯,通过不同温度条件下的拉伸实验对三明治预制坯的变形性能进行了评价,采用光学金相显微镜(OM)与扫描电镜(SEM)对拉伸变形过程微观组织的演化以及断裂失效后的断口形貌进行了观察,通过高温发泡实验对不同拉伸变形的三明治预制坯的高温发泡行为进行了研究。结果显示,随着变形温度的升高,三明治预制坯的峰值应力呈现了快速降低的变化趋势,而延伸率则呈现了稳步上升的变化趋势,芯板的断口形貌由脆性断裂特征转变为韧性断裂特征。三明治预制坯中破碎的氢化钛颗粒是其变形失效的裂纹源,在变形过程中,裂纹将由此产生并向基体扩展延伸,同时,这些裂纹对三明治预制坯的发泡行为产生不利的影响,将形成孔隙不均匀的微观缺陷。Aluminium foam sandwich precursor was prepared by powder pack rolling. The deformation properties of aluminium foam sandwich precursor were investigated by tensile test under different temperature. The microstructure evolution and fracture morphology were observed by optical microscope(OM) and scanning electron microscope(SEM) during tensile deformation process. The foaming behaviour of aluminium foam sandwich precursors with different tensile strain were studied by foaming test at high temperature. The results showed that the peak strength of aluminium foam sandwich precursors decreased rapidly, and the elongation increased steadily with deformation temperature increasing. The fracture morphology of core sheet converted from brittle fracture to ductile fracture. The broken TiH2 powder in the precursor was the origin crack of deformation failure, in which the crack would initiate and grow into the matrix during tensile deformation process. At the same time, the cracks had an adverse effect on foaming behaviour, and the micro defect of heterogeneous cell would be developed.

关 键 词：泡沫铝三明治预制坯 变形性能 失效机制 发泡行为 

分 类 号：TG3[金属学及工艺—金属压力加工]