John S

Audi reduced the cost by integrating the air bag halo surround with the retainer molding. They are using a thin wall SMA retainer that weighs less than conventional PC/ABS designs. Yes Victor, the pre-serrated PVC skin / urethane foam / SMA retainer is welded at the factory. Performance of the assembly was validated using high-speed data acquisition. The assembly must handle substantial deployment forces, therefore it is unlikely that Audi would trust a glue repair job done under unknown conditions. More likely than not, if the bag deploys the car will be written off. A short discussion of the air bag integration is given in SAE report 1999-01-0691.