大曲率复合材料结构的缺陷特征与超声检测

采用超声回波法对大曲率碳纤维增强树脂基复合材料零件进行超声A 扫描，并对缺陷进行定位。结合缺陷区域和非缺陷区域的细观形貌金相图、宏观表面状态以及厚度测量结果的对比分析，讨论了缺陷形态与其回波波形特征的对应关系，以及缺陷可能的形成原因。结果表明，缺陷在细观尺度上呈现多处分层、气孔和孔隙密集缺陷，在宏观尺度上表现为零件表面贫胶与厚度增厚。缺陷的性质与超声A扫描的检测结果相吻合，缺陷的位置集中在零件大曲率部位，其形成原因与复合材料制造工艺密切相关。

Characteristics of Defects and Its Ultrasonic Defection in Large Curvature Composites

Ultrasonic echo A scan method is adopted to scan large curvature carbon fiber reinforced composites and locate the defects areas. The results of metallographic microscopic analyses, thickness measuring and component surface conditions between healthy area and defect area are compared to investigate the relationships between the micro morphology of defects and ultrasonic pulse wave characteristics, as well as the causes of the defects. The delamination, air hole, and volume porosity in defect area result in poor resin in surface, thickening of the component and special ultrasonic propagation and attenuation. The defects located in large curvature position are closely related to the manufacturing process.