VARI成型厚度稳定与抽真空时间的研究

A STUDY OF THE STEADY THICKNESS BY THE VACUUM ASSISTED RESIN INFUSION PROCESS AND THE VACUUM KEEPING TIME

采用无接触式电涡流位移传感系统,对复合材料真空辅助成型过程中的厚度变化进行了实时监测。研究了在其他条件相同情况下,树脂粘度、充模距离、铺层厚度、铺覆导流网等对厚度稳定需要的最短抽真空时间的影响。结果表明,树脂注满并关闭树脂管以后,持续抽真空可有效提高真空辅助工艺成型纤维体积含量,且有利于减小沿树脂流动方向的厚度梯度;树脂粘度对厚度稳定所需要的最短抽真空时间影响最为明显,粘度越高需抽真空时间越长,充模距离、铺层厚度以及导流网对需要最短的抽真空时间影响相对较小。

The non-contact electric eddy current displacement sensor system was applied to real-time monitoring of the preform thickness change throughout the vacuum assisted resin infusion（VARI） infusion process. In the other same condition,the influence of the viscosity of resin,filling distance,layer numbers and the permeability on minimum vacuum time to get the steady preform thickness was investigated. The results show that,as the resin overflowed the mould and the resin inlet was closed,continued vacuumed time has an important influence on the thickness/fiber volume fraction,and is beneficial to the decrease of the thickness gradient along the direction of the resin flowing. The effect of the viscosity of resin has the primary influence on the minimum vacuum time for the steady thickness. The higher the viscosity,the longer vacuum time. The filling distance,layer numbers and the permeability has little influence.