闭孔泡沫铝力学特性及其在汽车碰撞吸能中的应用研究进展

汽车低能耗、安全和轻量化已经成为汽车领域研究的热点问题，闭孔泡沫铝作为一种轻质吸能金属材料，在低密度下具有良好的比刚度和比强度，同时具有良好的抗冲击性和能量吸收性，已逐渐引起汽车产业界地重视。简述泡沫铝单轴压缩试验中弹性模量、抗压强度、屈服强度、平台应力、致密化应变等参数的定义和试验标准；综述闭孔泡沫铝的本构方程的研究现状，重点讨论屈服面模型；总结泡沫铝的微观结构有限元建模方法，比较商业软件中集成的宏观材料模型。归纳吸能材料的特点，分析闭孔泡沫铝的吸能能力和抗冲击能力；综述应变率和冲击速度对泡沫铝吸能特性有无影响的研究进展，并对可能存在的影响进行解释。总结闭孔泡沫铝在汽车轻量化和碰撞安全性领域的应用，具体分析典型的案例。指出当前闭孔泡沫铝的力学特性及其在汽车结构中应用存在的问题与难点，总结并提出本研究领域可以借鉴的研究方向。

Progress on Research of Mechanical Properties of Closed-cell Aluminum Foams and Its Applications in Automobile Crashworthiness

Low energy consumption, safety and lightweight are the topic issues of the automobile industry. As a sort of lightweight and energy absorbing metallic material, the closed-cell aluminum foam has some advantage features of strong specific stiffness and specific strength with a low density, good impact resistance and energy absorbability, so it is brought to the new forefront of the automotive industry. The test criteria of uniaxial compression is described and the definition of several important parameters are clarified, such as Young modulus, compressive strength, yield strength, plateau stress and densification strain. The constitutive models of closed-cell aluminum foams are reviewed, among which the yield surface models are further emphasized. The modeling approaches of microstructure are summarized, and the macro material models integrated into commercial softwares are compared. Under summarizing the features of energy absorbing materials, the impact resistance and energy absorbability of closed-cell aluminum foams are especially analyzed. The influences of impact speed and strain rate are reviewed, and also some possible reasons are offered. The application of closed-cell aluminum foams in vehicle lightweight and crashworthiness is summarized, and several typical cases are analyzed. The problems and difficulties on understanding closed-cell aluminum foams’ mechanical properties and its applications in automobile structures are raised, and several feasible research directions are suggested.