THERMOMECHANICAL TREATMENT OF A HIGH-NB HIGH-V BEARING MICROALLOYED STEEL

The response of a Nb-V microalloyed steel to thermal-mechanical treatm ent is examined. Constant strain rate, isothermal compression tests of axially symmetrical samples, to a strain of unity, are used to determ ine the metal's response at high temperatures. Four-stage, constant tr ue strain rate compression of the samples is used to simulate partiall y the process of strip rolling. The loading is interrupted al various strains for ever shorter intervals. The resulting true stress-true str ain curves are used to examine the steel's response to interrupted loa ding. The ability of the microalloying components to retard to dynamic restoration processes, after an interruption, is observed. Microstruc tural observations indicate that the most important process parameter is the total strain.