(1) influence of temperature gradient. Temperature fluctuation has obvious influence on the high temperature mechanical properties of materials. · the temperature fluctuation will accelerate the creep process of materials and reduce the lasting strength. For example, 1.2Cr1Mo steel has 15-2-or. When the operating temperature of 15CrMo steel fluctuated at 485-53, the coil speed of the steel increased 3-4 times than that at 510℃. However, in the actual design, the temperature error of the parts of the expanding power equipment is allowed to be 25-50 *C.
(2) of heat resistant steel basket notch sensitivity gap caused by the stress concentration of persistent strength decided to lunch try to face the influence of temperature, the gap of geometry, durable plastic, heat treatment technology of steel and steel composition factors such as the dl} Fen hot steel under a certain temperature to the view out of the notch sensitivity, such as for 25 cr2mo1v steel, when temperature is 550 ℃ show a larger notch sensitivity; The persistent strength of the common band is significantly reduced. For different steels, the appearance of notch sensitivity is not exactly the same.
On 2018-08-08 11:45:46
