In many industries, the strenght to weight ratio is very important. For materials that are anisotropic in regard to this parameter, the MAS uses the average value. In some applications, such as machining, it is critical for the size or shape of the component to remain nearly constant while operating at different temperatures. Thus, it is important that the material used has a low coefficient of thermal expansion. This means for each deg increase in temperature, a one cm cube will expand a number of centimeters equal to the coefficient.
Elastic modulus is the stiffness of the material.
Thus, the higher the elastic modulus, the more stress is needed for the same deformation, the stiffer the material. Stiffness is important when a component must maintain its shape while under changing loads - such pistons in a combustion engine. The MAS uses the Brinell scale to measure hardness as it covers the entire range of material possibilities.