Aplicação do parâmetro de revenimento no tratamento térmico de chapas grossas de aços martensíticos de baixo teor de carbono

Abstract

In this work, correlations (empirical equations) were developed between the tempering parameter proposed by Hollomon-Jaffe and the mechanical properties of quenched and tempered heavy plates specific to the alloy design of a low-carbon martensitic steel (USI SAR 60T quality). These equations were obtained from production data and the respective process variables in the tempering heat treatment. These correlations made it possible to predict the values of mechanical properties (yield strength, tensile strength and total elongation) to be obtained as a function of the parameters of this treatment, i.e., time and temperature. They also made it possible to perform the reverse procedure, that is, to predict the tempering temperature to be applied for predetermined (targeted) values of mechanical properties. The previous knowledge of these process parameters, related to the particularity of the final application of the product/customer, provides a differential in the supply, as it allows to customize the heavy plate product, within the parameters of mechanical properties defined by the standard, in order to obtain the best performance in meeting the needs of customers. In turn, the graphs generated from the variables of the equations (tempering parameter x mechanical properties) are in good agreement with the behavior reported in the literature regarding the relationship between tempering temperature versus the obtained mechanical properties.