RECOVERY AND GRAIN-GROWTH IN A 2-PERCENT SI-0.3-PERCENT AL-0.003-PERCENT C-STEEL

The scope of our investigation covered the effect of carbon on the pro cesses of recovery and grain growth in cold-rolled non-oriented silico n steel, of laboratory and industrial provenance. Decarburized and non -decarburized cold-rolled electrical steels were annealed in a deoxidi zed lead bath in the temperature range from 550 to 800 degrees C. The microstructure was examined and average grain size assessed. The proce ss of recovery was investigated on specimens annealed at lower tempera tures by measurement of hardness. Industrially manufactured samples of non-oriented sheet were used for comparison. The sheets of both indus trial and laboratory manufacture were decarburized by annealing in wet hydrogen with different dew points at temperatures ranging from 800 t o 860 degrees C. The rate of decarburization was controlled by chemica l analysis of carbon.