Thermal Stress in Adhesive Butt Joints of Hollow Shafts in Steady Temperature Field.

Abstract

This study deals with the thermal stress and strain distributions in an adhesive butt joint which is composed of two hollow shafts. The butt joints are joined by an epoxide-type adhesive and kept at a constant temperature. In the analysis, when the shafts and an adhesive are replaced with finite hollow cylinders respectively, the temperature distribution in a joint is calculated based on the thermal conditions of the joint. Then, thermal stresses are analyzed as a three-body contact problem by the axisymmetric theory of elasticity. The effects of the ratios of Young's modulus, the coefficient of thermal expansion and the thickness of the adhesive on the thermal stress distribution at the interface between the adherend and adhesive are studied as general cases. Moreover, thermal stress in the joints of hollow and solid shafts under uniform temperature change is examined by numerical calculations as special cases of the joints. In the experiments, an adhesive is modeled by an epoxide disc-shape plate and the thermal strains are measured by strain gages which are mounted on the outer surface of the shaft close to the interface between the shaft and the epoxide plate. The analytical results of the thermal strain distribution are compared with the experimental ones measured by the strain gages and it is shown that they are in fairly good agreement.