The perfect interface pressure between the insulation of cable terminal silicone rubber (SR) and of cable body cross-linked polyethylene (XLPE) is the key to assure efficient and safe operation of cable terminal. The radial stress at the internal diameter of the cable terminal is the interface pressure between the cable terminal and the power cable

and the variation of temperature leads to the difference among the mechanical stress of the interface

the thermal stress of the interface and the stress relaxation characteristics of SR insulation

thus affecting the interface pressure of the cable terminal. In this paper

the influence of temperature on mechanical stress of the interface

the thermal stress of the interface and the stress relaxation characteristics of SR insulation is studied by single variable method

the variation of the linear expansion coefficient of SR and XLPE sample is measured by experiment

distributed to the three-dimensional model

and the interface radial stress at different temperatures is simulated by using the ultra-elastic and sticky elasticity structure model of SR insulation. The results show that the radial mechanical stress of the interface

namely the initial surface pressure

decreases with the increase of rise of temperature. The magnitude of the interface stress under different temperatures is different

the interface pressure magnitude varies with it and the maximum increase magnitude is about 21.87%. The stress relaxation speed of SR insulation accelerates with the increase of temperature

and the interface pressure decreases by about 5.63% after 50 years of operation of the cable terminal when the SR insulation temperature is at 70 °C for a long time.