CAJ | 학술논문

基于对2.5D编织复合材料细观结构的观察,提出了结构上更稳定的三维力学模型,反映了2.5D编织复合材料的结构.针对该模型,推导了纤维体积分数与几何参数之间的关系,并采用刚度平均法和有限元法预测了2.5D编织复合材料的等效力学性能,分析了弹性常数随纤维体积分数以及经密、纬密的变化规律.两种方法的预测结果均表明,倾斜角对弹性性能影响并不显著,但对材料内部的细观应力场有较大影响.理论预测与有限元结果吻合较好,从而验证了模型的有效性.
기우대2.5D편직복합재료세관결구적관찰,제출료결구상경은정적삼유역학모형,반영료2.5D편직복합재료적결구.침대해모형,추도료섬유체적분수여궤하삼수지간적관계,병채용강도평균법화유한원법예측료2.5D편직복합재료적등효역학성능,분석료탄성상수수섬유체적분수이급경밀、위밀적변화규률.량충방법적예측결과균표명,경사각대탄성성능영향병불현저,단대재료내부적세관응력장유교대영향.이론예측여유한원결과문합교호,종이험증료모형적유효성.
Based on the observation of the meso-structure of 2.5D braided composites, a three-dimensional mechanical model is presented, which is more stable and is able to reflect the structure of this composites. The relationship between the fiber volume and geometric parameters is deduced by using this model. The stiffness average method (SAM) and finite element method ( FEM ) are adopted to predict the effective mechanical properties. The elastic constants varying with the change of fiber volume, warp density and weft density are analyzed. Both of the predicted resuits show the camber angle does not noticeably affect the elastic properties, but has a notable impact on the mesostress field. The theoretical prediction is in accordance with the FEM results, which verifies the validity of the model.