Fiber/matrix debonding behavior of steel fiber composites is analyzed using a parametric finite element modeling procedure and compared with conventional composites with carbon and glass fibers. Cohesive surfaces are applied to fiber–matrix interface to simulate the debonding behavior, while the interface strength properties of steel fiber are obtained with and without surface treatment. The effect of various parameters on the debonding behavior is investigated, including stress concentrations, fiber diameter, fiber shape, and fiber volume fraction, using the parametric model. The influence of stress concentrations is determined to be much lower than the debonding strength. Debonding damage is more evident in larger fibers compared to smaller ones. Earlier and sudden interface separation is observed with the polygonal steel fibers compared to the circular ones. Increase in the fiber volume ratio increases the debonding opening distance but does not affect the opening angle significantly. The results can be useful for assessing possibilities to use steel fibers to increase toughness of the composites in comparison with glass and carbon reinforcement.

中文翻译：

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钢纤维复合材料中纤维/基体脱粘的微观数值研究

使用参数化有限元建模程序分析了钢纤维复合材料的纤维/基体脱粘行为，并与传统的碳纤维和玻璃纤维复合材料进行了比较。内聚表面应用于纤维-基体界面以模拟脱粘行为，而钢纤维的界面强度特性是通过表面处理和未经表面处理获得的。使用参数模型研究了各种参数对剥离行为的影响，包括应力集中、纤维直径、纤维形状和纤维体积分数。应力集中的影响被确定为远低于剥离强度。与较小的纤维相比，较大纤维中的脱粘损坏更为明显。与圆形钢纤维相比，使用多边形钢纤维观察到更早和突然的界面分离。纤维体积比的增加会增加脱粘开孔距离，但不会显着影响开孔角度。与玻璃和碳增强材料相比，这些结果可用于评估使用钢纤维提高复合材料韧性的可能性。