Abstract In order to study the durability of different kinds of pipes under high temperatures, 310S stainless steel, Incoloy 825 nickel-based corrosion-resistant alloy, 904L stainless steel, and TA16 titanium alloy were tested at room temperature and high temperature, and the high-temperature durability was tested at 350°C under different stress states. The results show that the mechanical properties of the four alloy tubes at high temperatures are significantly lower than those at room temperature, and the mechanical properties of TA16 titanium alloy are the lowest. The critical fracture strength of the four alloy pipes at 350°C is 529 MPa, 548 MPa, 526 MPa, and 380 MPa, respectively. Four kinds of alloy pipes were subjected to stresses of 527.51MPa, 544.85MPa, 523.58MPa, and 378.93MPa, respectively, at 350°C and held for 200h. The deformation rates in different holding periods were different due to the deformation mechanism and stress relaxation phenomenon. The displacement-time curve during the load-holding test was fitted, and the displacement of four kinds of pipes after the load-holding for 1000h was experimentally tested and predicted. The experimental test values and predicted values had good accuracy, and the errors were 0.418%, 1.34%, 0.65%, and 0.131%, respectively. According to the displacement-time curve, the displacements of the four kinds of tubes after three years of load holding were predicted. The prediction results showed that after three years of load holding, the four kinds of alloy tubes almost did not break, and the three-year average deformation rates were 6.511mm /a, 3.894mm /a, 5.258mm /a, and 3.860mm /a, respectively.
Yang et al. (Fri,) studied this question.