Debond Analysis of Honeycomb Sandwich Construction Substrates

Bubbly debonding occurred in the surface of the honeycomb sandwich construction substrates after thermal vacuum test. There were two kinds of debonding. One kind was debonding between polymide film and composite netting plate; another was debonding between composite netting plate and stiffened plate. Micro and macro observation was carried out on the debonding interface between polymide film and composite netting plate. The results indicated that polyimide film and composite netting plate bonded well. They debonded because of the external force. Micro and macro observation on the debonding interface between composite netting plate and stiffened plate was carried out. And FIR analysis, DSC testing and volatile determination of the adhesive film were also performed. The results indicated that composite netting plate and stiffened plate bonded poorly. The poor bonding is related to design or process control and has nothing to do with the quality of the adhesive film.