关键词: 本构模型, 泡沫铝, 碰撞, 吸能, 应变率

Abstract: 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.

Key words: impact, aluminum foam, constitutive model, energy absorption, strain rate