The high-temperature creep mechanism of G115 steel joint under the vacuum electron beam welding

Abstract

The welding joints of G115 steel were obtained from vacuum electron beam welding technology (VEBW), and their creep behavior was tested under the temperature at 630[Formula: see text]C, 650[Formula: see text]C and 670[Formula: see text]C with different stresses. According to the results, at the same temperature, the time of creep rupture decreases significantly with the test stress increasing, while the time of creep rupture declines significantly with the increased temperature at the same stress condition. The critical stress of creep for the welding joints at 630[Formula: see text]C, 650[Formula: see text]C and 670[Formula: see text]C is 115.28 MPa, 104.73 MPa and 96.98 MPa respectively. The stress index of welding joints between different temperature and stress conditions is about six, which indicates that the mechanism of creep deformation is controlled by the dislocation-climbing mechanism.