静态载荷下丝瓜络的能量吸收性能研究

为了深入了解丝瓜络的力学性能、能量吸收特性及其规律,对丝瓜络进行了轴向静态压缩试验,再通过拟合试验数据得到丝瓜络的单位体积的吸能量与密度的关系式。试验结果表明:丝瓜络的应力-应变曲线有3个阶段,即弹性阶段、屈服平台阶段和密实化阶段,屈服平台阶段的平台应力在0.15~0.50 MPa之间,密实化应变在70%左右,且其平台区较长,是一种理想的吸能材料;丝瓜络是一种对密度敏感的材料,其屈服强度、平台应力和单位体积的吸能量均随密度的增加而增加,密实化应变随密度增加而减小;丝瓜络单位质量的吸能量可以与泡沫铝材料相媲美。研究结果可作为设计基于丝瓜络结构的新型超轻仿生材料结构的基础数据

Study on Energy-Absorption Property of Luffa Sponge Under Static Load

A series of static-compressive tests was conducted to find out the rule of mechanical properties and energy absorption of luffa sponge with different densities. The experiments showed the stress-strain curve of luffa sponge material covered the elasticity region, the yield stage and the densification region. The plateau stress of yield stage ranged from 0.15 to 0.50 MPa, with the densification strain of luffa sponge being about 70 percent. A near constant plateau stress over a long strain range was ideal for energy absorption application. The research indicated the density had a great effect on its mechanical performance. With the increase in density, the yield strength, plateau stress and energy absorption capacity per unit volume of the luffa sponge were increased, while the densi cation strain was reduced. Finally, the empirical formula of energy absorption capacity varying with density was obtained by fitting test data, the theoretic result was proved well by comparison with the experimental results. Through calculation, the specific energy absorption of luffa sponge material was comparable to metallic cellular materials in a similar density range and could be used as the essential data for new ultralight biomimetic materials.