NUMERICAL MODELING OF THERMAL CHARACTERISTICS IN A MEMS-BASED MICRO-INITIATOR WITH INTERMETALLIC THIN FILM LAYERS
The use of intermetallic reaction from multiple micro-layers of binary metals could be the one feasible way to improve the ignition performance in addition to the ohmic heating and subsequent vaporization of thin-filmed metal bridge in MEMS-based micro-initiators for the initiation of energetic materials such as explosives or propellants. This study presents the electrothermal modeling and computations with a chemical reaction model of intermetallics between boron and titanium layers to predict the dynamic thermal response of microscale initiators. The one-dimensional approximation of thermal and atomic species diffusion through multilayers of device microstructure is employed as it is coupled with temperature dependent bridge resistance and additional heat release from intermetallic reactions. The paper discusses the effects of key design parameters such as micro-layer configuration and thickness, while examining the time-dependent ignition phenomena of thin-filmed bridge with intermetallic multi-layers.