Design and Performance Analysis of an All-Metal Phase-Change-Material Actuator for Enhanced Sealing and Displacement Output Characteristics

The phase-change-material (PCM) actuator, a non-pyrotechnic technology in aerospace, offers enhanced safety and convenience. This paper presents a novel PCM actuator featuring an all-metal construction to improve reliability and sealing. Characterized by high energy density and temperature-dependent actuation, the actuator’s displacement output characteristics (DOCs) are examined through visualization experiments. The results show the formation of a concave gap within the PCM upon cooling, which can be controlled by adjusting the cooling load and temperature to minimize its impact on displacement output. A two-dimensional physical model is developed to investigate how varying thermophysical parameters and boundary conditions affect the phase change process and DOC. The study finds that increasing the thermal conductivity of the PCM and surface heat flow enhances displacement velocity, although the effect diminishes at higher values. Additionally, reducing latent heat significantly boosts output velocity. For a fixed surface heat flow, changes in wall thickness have a minor impact, with velocity variation under 2%.