Dynamic testing of airbag fabric permeability and extensibility for depowered airbags

Woven textile fabrics are used in airbags to absorb the kinetic energy that is dissipated during an automotive crash. Energy dissipation is achieved through viscous airflow through the fabric pores and by biaxial stretching of the fabric. The synergistic effects of temperature, pressure, fabric weave, fabric finish and fabric denier is difficult to determine a priori. This study was proposed to gain better understanding of the performance of the airbag fabric and its properties under the hostile conditions of its deployment. Since airbag fabrics are being manufactured with different properties, it is important that these fabrics are evaluated before they are used for passenger restraint. Before this research effort, these fabrics were not tested at extreme conditions of temperature and pressure. The novel blister-inflation technique was used to evaluate the properties of these fabrics under biaxially stretching conditions. It was used to investigate the permeability-temperature-pressure drop relationship and biaxial stress-strain behavior of the fabrics.