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Addition of a safety control function to the micro-igniter (MI) and improvement of its output energy are key steps required to realize attitude control, state maintenance, and orbit adjustment of micro-aerospace vehicles using a micro-thruster. To solve the system misaction caused by traditional MI due to false triggering, a microelectromechanical system (MEMS) safety device based on Lorentz force is proposed, which can operate reliably under the driving condition of 0.5 T/0.5 A, and increase the safety control function for the MI. In addition, with the aim of addressing the problem that energy attenuation and unreliable ignition of the micro-thrusters are caused by the gap between the MI and the fuel, this paper proposes a hybrid integration process for an energy amplification element (Al/Ni energetic film) and an MI (Ni-Cr) to form a Ni-Cr@Al/Ni energetic MI (EMI). By optimizing the modulation ratio (3:2) and modulation period (75 nm) of the energetic film, the preparation of the integrated EMI is completed. Electrical explosion performance analyses of the micro-igniter are performed. Under 50 V/33 μF capacitor discharge excitation, TheAl / Ni energetic film can increase the output energy of MI by 17.54 mJ. Through the non-contact (2 mm) ignition capability test, the EMI can reliably ignite 30 mg B/KNO 3. Compared with the traditional MI, EMI has the advantages of high output energy per unit space and has a function of non-contact ignition. The EMI has strong application prospects in the aerospace vehicle launch and attitude adjustment field. [Display omitted] • A MEMS safety device based on Lorentz force is proposed. • The safety device can effectively isolate the energy output of the micro-igniter. • The Al/Ni energetic film can increase the output energy of micro--igniter by 17.54 mJ. • Through the non-contact (2 mm) ignition capability test, the energetic-micro-igniter can reliably ignite 30 mg B/KNO 3. [ABSTRACT FROM AUTHOR]

• A versatile microreaction system for handling high-solid-content fluids was set up. • The stability of fluids with Zr powder was investigated by UV–vis spectroscopy. • The surface reaction mechanism of Zr powder based on HF concentration was proposed. • The contradiction between the activity and sensitivity of Zr powder was reconciled. The regulation of energy release characteristics and safety of highly active metal fuels has attracted significant attention. In response to the limitations of using hydrofluoric acid (HF) to modify zirconium (Zr) powder in batch reactors, a microfluidic method coupling ultrasound and coaxial flow microreactors was proposed to achieve the control of the microstructure on the surface of Zr powder. The fluid flow and mixing characteristics in the microreactor were analyzed using on-line detection devices, leading to the determination of suitable fluid parameters. Through analysis of the reaction process between Zr and HF, a reaction model based on the HF concentration was established and subsequently verified through a microreaction system. The results indicate that the HF concentration greatly influences the morphology and composition of Zr powder, thereby determining the material and structural transformation of the Zr powder surface. The excellent thermal oxidation performance and electrostatic safety of HF-modified Zr powder were confirmed through thermal analysis and electrostatic discharge sensitivity tests. This study provides valuable insights for controlling the microstructure and properties of ultrafine Zr powder. [ABSTRACT FROM AUTHOR]