Lifetime of airbag inflators: Perspectives for a better understanding and prediction of aging mechanisms

The main focus of this work is to dissert and elaborate on how the lifetime of airbag inflators can be predicted and what needs to be understood from the mechanisms involved. First, the current problem with the standard testing of airbag inflators is identified to establish a baseline on how to address this issue. Then some of the work performed at ICT and some developed methods related to the aging are listed and briefly described: They range from propellant related investigations such as stability analysis of propellants, phase transition analysis with X-ray diffractometry, ballistic testing on aged propellants and newly developed mass flow characterization methods all the way to material related methods such as steel aging and oxidation characterization. After describing what have been done and investigated so far, it is possible to give an impression on the perspectives of how the problem can be addressed and what can be gained by bringing together different techniques and methods within a multidisciplinary approach to better understand the aging mechanisms, to better predict the aging processes in airbag inflators and to establish what is still needed to achieve both. The scope is not to give a specific solution for the current problem but to list which alternatives there are.