摘要
Al_(3)Ti具有低密度、高硬度等特点,然而,由于其具有较高的脆性,导致较小的变形下便会发生破碎。为了提高Al_(3)Ti的应用范围,受生物结构的启发,根据贝壳珍珠层、海螺壳和鱼鳞的几何结构,建立了Ti-Al_(3)Ti仿生有限元计算模型,研究了硬质相形状和加载速度对材料断裂的影响,从断裂行为、裂纹扩展过程和吸能效果等角度分析仿生复合材料的抗断裂机理。定义了形状系数,并对结构进行优化设计。结果表明,在准静态条件下,硬质相形状对仿珍珠层试样的断裂行为有显著影响。长方形硬质相能更好地抑制裂纹向载荷端扩展,从而提高试样的承载能力。形状系数在5.0左右的试样表现出最优的抗断裂能力和吸能效果。在动态冲击条件下,软质相抑制裂纹扩展的能力增强,使长方形试样的抗断裂能力和吸能效果得到进一步提高。
Al_(3)Ti is characterized by low density and high hardness,however,due to its brittleness,it is prone to fracture under smaller deformation.To improve the application range of Al_(3)Ti,inspired by biological structures,a biomimetic finite element model was established based on the geometry of shell pearl layer,conch shell and fish scale,and the influences of hard phase shape,as well as impact velocity,were investigated to analyze the fracture resistance mechanism of bionic composites in terms of fracture behavior,crack propagation process and energy absorption effect.A shape coefficient was defined to optimize the structure design.The results show that the shape of the hard phase has a significant effect on the fracture behavior of the bioinspired pearl-like layer specimens under quasi-static condition.The rectangular hard phase can better hinder the crack growth toward the load end,thus improving the load-bearing capacity of the specimen.The specimen with shape factor around 5.0 shows the optimal fracture resistance and energy absorption.Under dynamic impact conditions,the soft phase has increased ability to hinder crack growth,which further improves the fracture resistance and energy absorption effect of the rectangular specimen.
作者
修承东
王长峰
李冰
管仁国
XIU Chengdong;WANG Changfeng;LI Bing;GUAN Renguo(Continuous Extrusion Engineering Research Center of the Ministry of Education,Dalian Jiaotong University,Dalian 116028,Liaoning,China;Liaoning Key Laboratory of Near Net Forming,Dalian 116028,Liaoning,China)
出处
《高压物理学报》
CAS
CSCD
北大核心
2023年第4期87-95,共9页
Chinese Journal of High Pressure Physics
基金
国家重点研发计划项目(2022YFB3706801,2022YFE0137900)
辽宁省应用基础研究计划项目(2022JH2/101300003)。
