15 октября, 2015 
Pokraskin The CTE describes the temperature-dependent change in length and volume of a material. Various types of instrument can be used to measure the CTE of solid adhesives, including push-rod dilatometers or dilatometers with optical measuring devices. Within the glass transition range the CTE changes rapidly and causes additional internal stress in adhesively bonded joints, depending on the material and rigidity of the adherents and the elastic properties of the adhesive. Therefore, coefficients of linear thermal expansion are used, for example, for design purposes and to determine iffailure by thermal stress may occur when a solid body composed of two different materials is subjected to various temperatures. The test method ASTM E831 (Standard Test Method for Linear Thermal Expansion of Solid Materials by Thermomechanical Analysis) uses a smaller specimen and substantially different apparatus than test methods E 228 and D 696.
7.1.4
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