Temperature is a parameter which is important because of its influence on other material properties. Many temperature measurement techniques are available but few of them permit a direct visualization of surface temperature Variation. The Liquid crystal method is one of the rare methods that permits a complete color mapping of surface temperature and that is also fast enough to respond to surface temperature Variation on plates heated by cyclic bending. A mathematical model for irreversible mechanical heating of plates is developed to support the experimental investigation. The results, which include comparison of the theory and the experiment, show that liquid crystals allow good qualitative measurements and can lead, with certain precautions, to quantitative results.