Study on the Characteristics of Vacuum-Bag-Only Processed Composites by Prepreg/Fiber Interleaved Layup

In this study, the vacuum-bag-only (VBO) process was used to fabricate composite laminates by employing interleaved unidirectional fully impregnated prepreg and dry fiber. The mechanical test results show that the flexure strength, compression after impact (CAI) strength and compression before impact (CBI) strength of the carbon fiber composite laminate produced by this process are about 84%, 72% and 83% of the autoclave composite laminate, respectively. The CAI strength with impact energy of 8.5 J retained about 85.4% and 96.4% of the original strength, respectively, for the components fabricated by the interleaved layup VBO and conventional autoclave processes. Ultrasonic scanning was performed for the 50 × 50 cm² unidirectional carbon fiber composite to identify the void distribution. The results show that the composites fabricated by interleaved layup VBO process have good quality and low porosity. In the case of glass fiber composites, the hybrid laminate of this process was used to fabricate composite laminate in which unidirectional glass fiber prepregs and bidirectional dry woven glass fiber fabric are interleaved layup. The ultrasonic test results show that the internal pores of this composite laminate are very few, and the quality is good. The feasibility of applying the process to different materials or woven materials was demonstrated.