The thermo mechanical processing to obtain ferritic steels with ultra-fine grains

摘要

The thermo mechanical processing to obtain ferritic steels with ultra-fine grains. To generate the low carbon steel with ultra-fine grains, the product target refining needs through two phases, in this order: microstructural conditioning and thermomechanical processing.The step of conditioning microstructural resides in season play in the oven preferably 900 u00b0 C for 30 minutes encharque and quenching in water to obtain a structure martensitica thin.The step of thermomechanical processing is based on heat the piece at a temperature between 700 and 1400 u00b0 C for 12 minutes and perform 3 passes rolling reduction de2o% and strain rate of the 1 s - 1 in each pass, to return to the oven between the passes under the same temperature range (700 - 760 u00b0 C) and residence time in the furnace of 6 minutes.To finish the process of refining grain, make a piece preferably annealing at 800 u00b0 C for 1 hour and cooling water.