对曲面变厚度编织复合材料进行金相观察,分析纤维分布特点和主要缺陷类型,并对孔隙形态进行统计分析。研究结果表明:编织复合材料变厚度区纤维以90°铺层为主,0°铺层沿轮廓分布,且存在纤维层分裂现象;出现大量的富脂区,并有微裂纹存在,纤维层间有分层现象;孔隙主要分布在树脂区和层间,以小的球形为主,富脂区域容易出现集中孔隙;孔隙数量的增加是导致孔隙率增加的主要原因,随着孔隙率增加,孔隙长度、宽度和面积均增大,孔隙宽长比基本相同,孔隙形状因子减小,且当孔隙率大于1.5%时,形状因子减小加剧;孔隙长度、宽度与孔隙含量之间均存在近似对数正态关系。
Analysis of distribution features of fibers and main defects was made, and the morphology of pore in hybrid fibers braided composite with variable thickness was statistically studied based on metallographic observation. The results show that the variable thickness area is filled with fibers of 90° laminate, and 0° laminate is displayed along the boundary with fiber division. Large area rich resin occurs with micro-crack, as well as layered between laminates. Small spherical pores mainly distribute in resin and layered, and concentration pores distribute in rich resin area. Increasing pore quantity is the main reason for increased porosity, While porosity increases, the average length, width and area of pores increase, but the ratio between width and length is unchanged. As well, the shape factor decreases, and it decreases faster when porosity is larger than 1.5%. Lognormal distribution relationships exist between length or width and porosity.