Research On Design,Fabrication And Performance Of Fire Transmission Sequence Based On PyroMEMS Safe And Arm Mechanism

A fire transmission sequence based on Pyrotechnical Micro Electro Mechanical System(PyroMEMS)safe and arm(S&A)mechanism is designed in this paper,which can meet the development requirements of the miniaturization of advanced pyrotechnics.The volume of the fire transmission sequence is less than 2cm3,and the PyroMEMS S&A mechanism is built in the fire transmission sequence,so as to realize the function of S&A and fire.On the basis of structural design,a principle prototype of fire transmission sequence was fabricated,and the performance of the principle prototype was tested.The results are as follows:(1)According to the design principle of the fire transmission sequence,the Semi-Conductor Bridge(SCB)fire transmission sequence and the Low Temperature Co-fired Ceramic(LTCC)fire transmission sequence.The LTCC igniter are designed at the same time.SCB fire transmission sequence consists of SCB ignition circuit layer,input charge layer,PyroMEMS S&A mechanism layer and output charge layer;LTCC fire transmission sequence consists of LTCC base,PyroMEMS S&A mechanism layer and output charge layer;SCB,Micro Semi-Conductor Bridge(MSCB)and Ruthenic Oxide(RuO2)was designed。(2)The Micro-Electro-Mechanical-System(MEMS)technology,the LTCC technology and the precision machining technology are used to fabricate the principle prototype of the fire transmission sequence.Using silicon material to fabricate SCB ignition circuit layer and PyroMEMS S&A mechanism layer;The input charge layer and the output charge layer is made of stainless steel;Elastic beam using 65Mn steel preparation and processing;This paper analyses the disariming process of PyroMEMS S&A mechanism layer,and establishes a mathematical model for the amount of gas generator to disarming.(3)Ignition performance of SCB,MSCB and RuO2 was tested.The ignition conditions of SCB,MSCB and RuO2 were determined respectively.The ANSYS Workbench17.0 software is used to simulate the RuO2,simulation results show that in the corner temperature of RuO2 can be increased to more than 1300℃ under 20V;Potassium Picrate/potassium perchlorate powder(K1K powder)was used as the gas generator,and through experiments test concluded that the minimum dose of the principle prototype task is 6.5mg and the minimum pressure is 49.7MPa;Using Boron/potassium nitrate(B/KNO3)for experiment,and the experimental results show that the SCB fire transmission sequence can not realize the function of S&A and fire,and the LTCC fire transmission sequence can complete S&A and fire function.