But, if you are serious about learning Italian - and even before you buy or subscribe to any expensive courses (except, obviously, GamesforLanguage.com's Italian Story, which is FREE!) - you may want to learn more about Benny's approach by clicking on his explanation of Why Italian is easy!.
Coefficient of thermal expansion. The coefficient of thermal expansion describes how the size of an object changes with a change in temperature. Specifically, it measures the fractional change in size per degree change in temperature at a constant pressure. Several types of coefficients have been developed: volumetric, area, and linear.
For instance, thermal conductivity of the shielding gas is important because high heat can influence the shape of the weld bead and the speed of the weld. If a welder elects to use another gas instead of helium, he or she might lose some of that ability to deliver high heat input during the weld.