Abstract: When the composite parts with corner are manufactured by autoclave process, due to structural reasons, there is a pressure difference in the corner area of composite parts, resulting in a thicker concave corner and a thinner convex corner after curing. The hat stringer was taken as the research object to analyze the causes and key influencing factors of the thickness deviation of the corner of the composite parts manufactured by the autoclave process, and the experimental verification was carried out. According to the results of theoretical analysis and experimental verification, the thickness deviation of the corner is directly related to the ratio of the radius and the thickness of the corner (R/t). The smaller the R/t value, the greater the thickness deviation of the corner. When the R/t value is determined, the thickness deviation and forming quality of the corner can be significantly improved by reducing the thickness and bridging risk of the auxiliary materials in the corner zone during the curing package of the test parts, such as using the cut glass fabrics instead of the whole breather as the gas-conducting material during the curing of the parts.

Key words: composite, autoclave process, hat stringer, corner, thickness