STATIC RECRYSTALLIZATION AND GRAIN-GROWTH OF A STAINLESS AUSTENITIC STEEL

Static Recrystallization (SR), is here used as a way to get an ASTM [1 ] grain size of 3 or so. Making a prediction of the effect of both def ormation and temperature on the kinetics of the SR phenomena is the fi rst step toward a global microstructure prediction at the end of the m anufacturing sequence. It is the main goal of the study here after des cribed. In this study, we did hot compression tests (950-1200 degrees C) and analyzed them in terms of recrystallized fraction (quantitative metallography) using to classic Avrami equation. We observed some lim e exponents (k) smaller than 1, which goes against Avrami's theory, wh ich only describes equal or above 1 exponents. The time for half recry stallization (t(0.5)) has also been determined, according to C.M. Sell ars method and reached a satisfactory, experiment-calculation agreemen t. After completion of the recrystallization, the Grain Growth phenome non occurs. Thanks to a wide study of thermal annealings, we found a A = A, + alpha.t(n) type of equation, where alpha is a variable involvi ng Q, an activation energy, through an Arrhenius equation.