Investigating elastic properties of materials at high pressure and temperature in the Paris-Edinburgh cell

               Knowledge of the elastic properties of materials such as the bulk, Young’s, and Shear moduli and Poisson’s ratio is critical when designing items like tools, machinery, and structures. Further, if items will encounter conditions of extreme stress and/or temperature, it is important to understand material properties at these conditions to optimize design. To determine the elastic constants of materials, we perform sound speed and density measurements as a function of pressure and temperature in a Paris-Edinburgh-style large volume hydraulic pressure cell in situ at the Advanced Photon Source. The pulse-echo method is employed to obtain ultrasound time-of-flight, while X-ray radiography is used to measure sample dimensions, and  X-ray diffraction is used to determine density and pressure. Our experimental apparatus attains sample conditions of up to 1000 °C and 7 GPa. In this presentation, I will outline the experimental apparatus, data acquisition, and analysis used to determine elastic constants as a function of pressure and temperature. Recent experimental results from metal and polymer samples will be presented to highlight the usefulness of the technique across a broad range of material systems.