Comparison of different methods for austenite grain size estimation

Grain-size evaluation methods according to grain linear dimensions and areas are compared. The investigation was made on 12KhN3A steel specimens quenched from different temperatures. The curves of the grain linear-size distributions show a distinct maximum. The occurance of a small amount of grains of different sizes in the structure has no effect on these curves. The curves of the area relative weights have been found to be the most objective alloys grain composition indices