Research Information System
SAMPE 2025 Conference and Exhibition, Indiana, United States Of America, 19 - 22 May 2025, pp.430, (Full Text)
The durability of repaired CFRP components under environmental conditions such as high humidity and temperature is critical for reliable long-term operation. This study investigates the effects of temperature and moisture on the repair strength of prepreg and wet lay-up repairs performed on M21/AS4C carbon/epoxy fabric panels. A series of wet lay-up and prepreg step-repaired specimens produced according to standardized aerospace procedures were tested under uniaxial tension. For each case, dry specimens and hot-wet specimens immersed in water at 70°C for 14 days were considered. The experimental measurements on 3.8° scarf angle repairs showed that the strength recovery could be as high as 68% for the prepreg repairs and 59% for the wet lay-up repairs for unconditioned specimens. The moisture and humidity exposure did not have a significant impact on the strength of the prepreg-based repairs. Wet lay-up repaired specimens, on the other hand, showed a 30% reduction in strength upon exposure to humidity and temperature. The results show that prepreg repairs should be preferred over wet lay-up repairs for the long-term reliable operation of repaired components.