Advanced sheet molding compounds (A-SMC) are a new generation of alternative materials to steels for applying in automotive structures. It contains a thermoset matrix involving mineral charge (CaCO₃) reinforced with a high fraction of discontinuous bundles of glass fibers (around 50% in mass) compared to the other types of SMC composites. The crashworthiness evaluation and multi-scale mechanical characterizations of this automotive material is essential. In this study, at first, the microstructure of A-SMC composite was investigated by Scanning Electron Microscopy (SEM), ultrasonic analysis, and X-ray micro-tomography. Two configurations’ plates of Randomly Oriented (RO) and Highly Oriented (HO) were analyzed under quasi-static tension, compression, and shear loadings. To study the effect of fiber orientation, for HO plate, two fiber directions were chosen: HO-0° (parallel to the Mold Flow Direction (MFD)) and HO-90° (perpendicular to the MFD). Strain rate effect (from 0.25 s⁻¹ to 10 s⁻¹) on shear properties and visco-damage behavior of A-SMC composite has been studied. For this purpose, a new setup for shear testing was designed after optimization via ABAQUS FE code to achieve constant strain rate. HO-0° samples represented higher strength in tension and compression loadings, unlike shear loading compared to RO and HO-90° samples. A multi-scale damage study confirmed that predominant damage mechanism is decohesion at fiber/matrix interface under tension, compression, and shear loadings.

高级片状模塑料 (A-SMC) 是用于汽车结构的新一代钢材替代材料。它包含一个涉及矿物电荷的热固性基质 (CaCO ₃) 与其他类型的 SMC 复合材料相比，使用高比例的不连续玻璃纤维束（质量约为 50%）增强。这种汽车材料的耐撞性评估和多尺度机械特性是必不可少的。在这项研究中，首先通过扫描电子显微镜 (SEM)、超声波分析和 X 射线显微断层扫描研究了 A-SMC 复合材料的微观结构。在准静态拉伸、压缩和剪切载荷下分析了随机取向 (RO) 和高度取向 (HO) 两种配置的板。为了研究纤维取向的影响，对于 HO 板，选择了两个纤维方向：HO-0°（平行于模流方向 (MFD)）和 HO-90°（垂直于 MFD）。应变率效应（从 0.25 s ^-1到 10 s ^-1) 对 A-SMC 复合材料的剪切性能和粘损行为进行了研究。为此，在通过 ABAQUS FE 代码优化后设计了一种新的剪切试验装置，以实现恒定应变率。与 RO 和 HO-90° 样品相比，HO-0° 样品在拉伸和压缩载荷方面具有更高的强度，这与剪切载荷不同。一项多尺度损伤研究证实，主要的损伤机制是纤维/基质界面在拉伸、压缩和剪切载荷下的脱聚。