纤维环向缠绕复合材料气瓶冲击阻抗性能研究

IMPACT RESISTANCE OF FIBER HOOP-WRAPPED COMPOSITE CYLINDERS

新能源汽车用复合材料气瓶采用复合材料/金属混杂结构,其冲击损伤特性与采用纯复合材料结构有很大的不同,本文结合复合材料气瓶和试板模拟试验,采用冲击能量吸收率、分层损伤扩展阻力、剩余强度比衰减指数等参数作为其冲击阻抗性能的评价指标。采用不同的支撑夹具对玻纤/环氧单向板进行落球冲击试验,以模拟复合材料气瓶的不同材质内胆对纤维缠绕层冲击损伤的影响。研究发现,在一定冲击能量作用下,改变复合材料/金属混杂结构的形式能使其冲击能量吸收率发生变化,并可提高层合板的冲击损伤临界值,即提高其冲击承载能力;冲击能量吸收率越高分层损伤扩展阻力越小,且含冲击损伤层合板的剩余强度衰减越快。因此在设计复合材料气瓶时,需要考虑复合材料/金属混杂结构对分层损伤扩展阻力和冲击能量吸收率的影响。

The composite / metal hybrid structure is widely used in composite cylinders of new energy vehicles, which has different impact damage characteristics compared with pure composite structure. This paper, combining both the tests of composite cylinder and test panel, evaluates impact resistance performance with parameters such as： impact energy absorption rate, delamination extension resistance and attenuation factor of the residual strength ratio. The experiments of falling ball impact with various support fixtures and glass fiber/epoxy unidirectional lami- nates are carried out to simulate how different liner materials of composite cylinders affect the impact damage degree of fiber winding layers. It is found that, under certain impact energy, changing composite / metal hybrid structure leads to the change of impact energy absorption rate and increases critical value of impact damage, namely, bear load impact capacity. The higher impact energy absorption rate will reduce delamination extension resistance, and the residual strength of laminate with impact damage will attenuate faster. As a result, the effect of delamination extension resistance and impact energy absorption rate should be taken into consideration while designing composite cylinders.