Elevated-Temperature Elastic Properties of Alloys 709 and 617 Measured by Laser Ultrasound

Non-contacting laser ultrasound is used to measure Young’s modulus, shear modulus, and Poisson’s ratio as functions of temperature for Alloys 617 and 709. These alloys are of interest for structural applications in advanced nuclear reactors. Design rules for the construction of elevated-temperature nuclear components are presented in Section III, Division 5 of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code. The ASME B&PV Code for each material provides Young’s modulus values tabulated as a function of temperature and a single, temperature-independent Poisson’s ratio value. Elastic properties characterized by laser ultrasonics for Alloy 617 are in good agreement with data collected using an American Society for Testing and Materials (ASTM) standard resonant frequency technique and values reported from literature, demonstrating its accuracy. The shear modulus and Poisson’s ratio as functions of temperature for Alloy 709 have not been reported previously. Laser ultrasonics is well suited for determining temperature-dependent elastic properties, and the method offers the ability to perform measurements on small irregularly shaped specimens.