报告会简介
报告人：Lin Ye教授
时间：2018年4月11日（星期三）9：30
地点：友谊校区国际交流中心国一会议室
题目：“Liquid Armour” – How Much Energy It Can Absorb?
冲击动力学讲坛简介
冲击动力学讲坛由云顶集团7610官方网站冲击动力学及其工程应用国际联合研究中心建立的一个学术交流平台。云顶集团7610官方网站冲击动力学及其工程应用国际联合研究中心由西工大与荷兰代尔夫特理工大学、法国巴黎第六大学、澳大利亚悉尼大学、美国阿克伦大学和澳大利亚斯威本科技大学等国际知名高校共同建立，2017年获国家国际科技合作基地认定。中心围绕航空航天重大力学问题以及“大飞机”和“两机专项”等重大科技专项的工程需求，致力于先进结构与材料的动态响应、破坏机理等重大科学问题及工程化应用研究，与国际伙伴合作形成了一批具有国内领先和国际先进水平的联合成果，解决了飞行器结构及航空发动机抗离散源撞击等国际性难题，相关成果已在ARJ21、C919、蛟龙AG600等国家重点型号飞机抗冲击设计中得到应用。
冲击动力学讲坛面向全校师生，不定期邀请冲击动力学领域的国际著名学者，以邀请报告或学术沙龙的形式分享科研成果和进展、研究经验和心得，提升云顶集团师生尤其是青年教师在冲击动力学、航空宇航等学科领域的基础性和前沿性，同时促进云顶集团7610官方网站国际合作交流工作的发展。
内容简介
Shear thickening fluids (STFs), are concentrated colloidal suspensions composed of non-aggregating solid particles suspended in fluids. These suspensions have the property of an abrupt increase in the fluid viscosity when the shear rate reaches its critical value.One promising application of STFs is to develop passive, energy-absorbing systems, in which STFs can divert or dissipate the energy via viscosity, friction or “plasticity” depending on deformation modes and rates. It was reported the Kevlar fabrics impregnated with a STF enhance ballistic penetration resistance, frequently referred to as“liquid armor”,thus offering flexible body armour with significantly reduced thickness, though the conflicting results were also reported.
This work established some methods and approaches to investigate and characterizetheenergy-absorbing/dissipation properties of a STFsystematically after the shear-thickening transition. The STF selected for this work is composed of 58 vol.% dispersion of styrene/acrylate particles in ethylene glycol. The lap-shear and double-cantilever-beam specimens with the STF as adhesive layer were adopted to characterize shear strength, braking energy and mode-I fracture energy of the STF at different shear or crack opening displacement rates. The load-displacement curve as well as the high-speed video recording confirmed that the STF showed a “solid” behaviour at high rates by developing a brittle shear failure or stable crack extension that corresponds to a brittle fracture behaviour. The results indicated that the shear rate has a significant effect on the lap shear strength (with a plateau value of 0.3 MPa) and the total braking energy (with an average value of 4 kJ/m2) of the STF, while the displacement rate and the STF thickness have a significant effect on the mode-I fracture energy of the STF. The fracture energy increases as an increase in the displacement rate, while a plateau value of 240 J/m2was observed at high rates. Moreover, the studies were conducted to quantitatively characterize the energy absorption capacity of the STF under penetration impact and pull-out fracture at different impact or pull-out speeds. The results confirmed that the penetration rate again has a significant effect on energy absorbing capacity of the STF. In comparison with the energy absorbing behaviour of some cellular materials in literature, the STF outperforms a polyurethane foam in terms of penetration energy absorbing capacity.
报告人简介
Lin Ye教授为澳大利亚悉尼大学航空航天、机械和机电工程学院教授，悉尼大学先进材料技术中心主任。他于1982年在哈尔滨工程大学获得学士学位，1984年和1987年在北京航空航天大学分别获得硕士和博士学位，1988年加入西安交通大学担任讲师，1990-1992年间，在德国TUKInstitute for Composite Materials (IVW GmbH)实验室担任Alexander von Humboldt研究员。1992年7月加入悉尼大学，主要研究复合材料科学与技术、智能材料与结构、纳米材料和纳米复合材料、结构完整性和耐久性。Lin Ye教授于2005年当选为澳大利亚技术和工程学院（Australian Academy of Technology and engineering, ATSE）院士。目前担任Composites Communications副主编、CompositesScienceand Technology等一系列国际杂志编委。编著或参编13部书,发表SCI论文249篇和102篇会议文章。
