Characterisation of aluminum metal-matrix composite (MMC) for lightweight sapce optics application - A study of thermal expansion behaviour of MMC in simulated space thermal enviornment

摘要

Application of advanced composite material for lightweight mirror for space optics needs to know the exact thermal expansion behaviour of the composite in space thermal environment. In this paper, thermal expansion behaviours of plasma thermal sprayed and powder metallurgy processed ceramic particulate reinforced aluminum metal-matrix composites in simulated space thermal environment were studied. Thermal cycling was found to cause hysteresis and non-linear thermal expansion responses to the composites when the thermal stress within the composite exceeds the yield strength of the matrix, and subsequently causes matrix plastic flow.