Abstract:
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.