A fundamental understanding of structure-property relationship of carbon fiber reinforced polymer (CFRP) composites fabricated by selective laser sintering (SLS) is essential to provide guidance to improve the mechanical properties in this promising additive manufacturing process. In the present study, we propose a new computational framework to evaluate the mechanical behavior of SLSed CFRP based on the representative volume element (RVE) model. Firstly, a new voxel-based fiber packing algorithm is proposed with the three-dimensional fiber orientation tensor to describe the fiber distribution. The porosity generated in the manufacturing process is also considered by adding spherical voids in the matrix region. In order to remove the artificial stress concentration induced by the voxel-based algorithm, a python script is developed to regenerate the geometries of different phases with conforming mesh. Meanwhile, the constitutive models of different phases in SLSed CFRP, i.e., matrix, fiber and interface, are established according to the material characteristics. Next, the proposed computational framework of SLSed CFRP is validated by the X-ray computed tomography (XCT) measurements and tensile tests of a representative SLSed carbon fiber/polyamide 12 (CF/PA12) composite. The effects of fiber volume fraction and fiber orientation distribution on the mechanical behavior of SLSed CF/PA12 composite are further quantitatively explored and ranked with regards to their influence on stiffness and failure strength.

对通过选择性激光烧结（SLS）制成的碳纤维增强聚合物（CFRP）复合材料的结构-性能关系的基本理解，对于提供指导以改善这种有前途的增材制造工艺中的机械性能至关重要。在本研究中，我们提出了一个新的计算框架，以基于代表性体积元（RVE）模型评估SLSed CFRP的力学性能。首先，提出了一种新的基于三维像素的纤维堆积算法，利用三维纤维取向张量来描述纤维分布。还可以通过在基体区域中添加球形空隙来考虑制造过程中产生的孔隙率。为了消除基于体素的算法引起的人为应力集中，开发了一个python脚本，以使用一致的网格重新生成不同阶段的几何形状。同时，根据材料特性，建立了SLSed CFRP中不同相的本构模型，即基体，纤维和界面。接下来，通过代表性的SLSed碳纤维/聚酰胺12（CF / PA12）复合材料的X射线计算机断层扫描（XCT）测量和拉伸试验验证了SLSed CFRP的拟议计算框架。进一步定量研究了纤维体积分数和纤维取向分布对SLSed CF / PA12复合材料力学性能的影响，并根据它们对刚度和破坏强度的影响进行了排名。纤维和界面是根据材料特性确定的。接下来，通过代表性的SLSed碳纤维/聚酰胺12（CF / PA12）复合材料的X射线计算机断层扫描（XCT）测量和拉伸试验验证了SLSed CFRP的拟议计算框架。进一步定量研究了纤维体积分数和纤维取向分布对SLSed CF / PA12复合材料力学性能的影响，并根据它们对刚度和破坏强度的影响进行了排名。纤维和界面是根据材料特性确定的。接下来，通过代表性的SLSed碳纤维/聚酰胺12（CF / PA12）复合材料的X射线计算机断层扫描（XCT）测量和拉伸试验验证了SLSed CFRP的拟议计算框架。进一步定量研究了纤维体积分数和纤维取向分布对SLSed CF / PA12复合材料力学性能的影响，并根据它们对刚度和破坏强度的影响进行了排名。