Thermal Stresses • Occur due to: Thermal stress 
{"Image DocumentName": "Thermal Stresses \u2022 Occur due to: Thermal stress \uf03d\uf020\uf073", "Image ImageDescription": "-- restrained thermal expansion/contraction. -- temperature gradients that lead to differential dimensional changes. Thermal stress. \uf03d\uf020\uf073 Upon heating, the stress is compressive (\u03c3 < 0), because rod expansion has been constrained. Upon cooling, the stress is tensile (\u03c3 > 0). Ex-Prob 19.1: A brass rod is stress-free at room temperature (20\u00baC). It is heated up, but prevented from lengthening. At what temperature does the stress reach -172 MPa? (For brass, assume a modulus of elasticity of 100 GPa and the coef. Linear thermal exp. = 20x10-6 (C0)-1)", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}