SW220/430LV在不同温度下热-力压缩行为研究和表征建模

Thermal-mechanical compression behavior and characterization modeling of SW220/430LV at different temperatures

对S2/430LV进行热-力联合作用下压缩性能试验研究,重点揭示S2/430LV在20~180℃压缩损伤失效机制及强度/模量随温度变化规律;提出一种基于Ha-Springer模型的分段曲线拟合方法,并对强度/模量随温度变化规律进行预报。研究表明:在热-力联合作用下,压缩强度和模量随着温度升高而降低,但模量保留率高于强度;随着温度增加,试样最终失效模式发生改变,在100℃之前,试样呈整体剪切失效模式,纤维束发生扭结,并伴随纤维断裂和损伤路径出现断口;但在100℃以后,最终失效模式表现为树脂基体剪切损伤,而纤维织物形态基本不变;强度和模量随温度变化规律呈“S”形趋势,其中强度-温度曲线在20~80℃为凸曲线,80~180℃则为凹曲线;模量-温度曲线在20~100℃为凸曲线,100~180℃为凹曲线;提出了一种基于Ha-Springer模型的分段曲线拟合方法,并利用Origin软件对强度/模量随温度变化规律进行预报,预报结果与试验结果高度吻合,且吻合程度优于Mahieux模型。

The compressive performance test of S2/430LV under the combined effect of heat and force was carried out,with a focus on revealing the compression damage failure mechanism and the variation law of strength/modulus of S2/430LV from 20 to 180℃.A segmented curve fitting method based on the Ha-Springer model was proposed,and the variation law of strength/modulus with temperature was predicted.The study shows that under the combined effect of heat and force,the compressive strength and modulus decrease with the increasing temperature,but the modulus retention rate is higher than that of strength.With the increase of temperature,the final failure mode of the sample changes.Before 100℃,the sample shows an overall shear failure mode,with fiber bundles twisting and accompanied by fiber fracture and damage path fracture.However,after 100℃,the final failure mode is manifested as the shear damage of resin matrix,while the fiber fabric morphology remains basically unchanged.The strength and modulus exhibit an"S"-shaped trend with temperature,where the strength-temperature curve is a convex curve in the range of 20-80℃and a concave curve in the range of 80-180℃;The modulus-temperature curve is a convex curve in the range of 20-100℃and a concave curve in the range of 100-180℃.A segmented curve fitting method based on the Ha-Springer model was proposed,and Origin software was used to predict the variation of strength/modulus with temperature.The prediction results are highly consistent with the experimental results and the degree of agreement is better than that of the Mahieux model.