AUSTENITE GRAIN-GROWTH BEHAVIOR OF MICROALLOYED AL-V-N AND AL-V-TI-N STEELS

The austenite grain growth behaviour of microalloyed AI-V-N and Al-V-T i-N steels has been studied. Estimations of austenite grain size for A l-V-N steels by several different grain growth inhibition models demon strated that the best match to experimental results can be obtained fr om Gladman and Rios equations and it is AlN that controls the austenit e grain size. The experimental and calculated results indicated that t he drag force of plate-shaped AlN particles probably depends on their orientation and austenitising temperature. A modified Gladman model, w hich considers the effects of complex arrays of different types of par ticles on the stabilized austenite grain size, can be used to predict the austenite grain size and particle size for an Al-V-Ti-N steel when the combined effect of AlN and TiN is considered.