AbstractParticle reinforced composites are being considered, in applications requiring an increased elastic modulus, over unreinforced alloys, and in many cases the increased modulus is also required at elevated temperatures. In this paper the temperature dependence of the elastic modulus is examined using a laser ultrasound technique. It is demonstrated that this non-contact method is capable of measuring the modulus up to temperatures of 700 K and is sufficiently sensitive to detect microstructural changes in some instances. In composites which have a stable microstructure over the temperature range from room temperature to 700 K, the elastic modulus decreases linearly with increasing temperature.MST/1894