Three of the main techniques used for CTE measurement are dilatometry, interferometry, and thermomechanical analysis. Optical imaging can also be used at extreme temperatures. X-ray diffraction can be used to study changes in the lattice parameter but may not correspond to bulk thermal expansion.

What do you mean by coefficient of volume expansion?

Definition of coefficient of expansion : the ratio of the increase of length, area, or volume of a body per degree rise in temperature to its length, area, or volume, respectively, at some specified temperature, commonly 0° C, the pressure being kept constant.

What is the coefficient of volume expansion of solids?

Volume Expansion: Volume expansion is defined as the increase in the volume of the solid on heating. With a change in temperature ∆t the change in volume of a solid is given by ∆v=Vy∆t where the coefficient of volume expansion is y.