The purpose of the diploma thesis was to investigate the influence of four different procedures for continuing the rolling process after the elimination of technological
stagnation on the formation of thermal cracks in the rolls. The test was performed on the Gleeble 1500D thermo-mechanical metallurgical state simulator. Samples were
taken from cylinders with an elevated chromium value. Cracks are formed due to compressive and tensile stresses that occur due to heating and cooling of the material. The crack itself spreads along the carbides, and its growth is further
accelerated by the oxides. The samples were fatigued at temperatures of 500 °C, 600 °C and 700 °C. We simulated four possible ways of cooling the rolls after a standstill and resuming rolling: after stagnation with air and at the end with air, after stagnation with water and at the end with water, without cooling after stagnation and at the end with air and without cooling after stagnation and in the and with water. With the use of microscope, we counted the number of cracks, calculated the crack density and determined the average length of the cracks.
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