Análise das propriedades mecânicas e da energia de falha de empilhamento em aços alto manganês

Abstract

The growing study of high-manganese austenitic steels has intensified in recent years. Requirements of properties at low temperatures have motivated the study of the mechanical behavior of these alloys in a cryogenic environment, while intensifying the study of the type of deformation mechanism that these steels can suffer as a function of the stacking fault energy, simulated through of the most varied thermodynamic models proposed. The present work evaluated the influence of the temperature and the distribution of alloying elements on high manganese steels with Si, Al and Cr at 25 ° C and -196 ° C (cryogenic temperature) through the analysis of data obtained from mechanical tensile tests and Charpy at the respective temperatures using the technique of analysis of variance for two factors for data treatment. The results showed that the cryogenic temperature intensifies the yield strength and resistance in a significant way which reinforces the idea of the use of the high manganese in cryogenic environments, in contrast, the loss of tenacity and ductility occurs. Regression and surface models were constructed to simulate results of mechanical properties. The thermodynamics of stacking fault energy was used to simulate the value in temperature ranges from cryogenic to very high values and how the chemical, magnetic and interfacial contributions interfered in the stacking fault energy. The chemical elements were also evaluated, where Al, C, Mn contributed to the increase of stacking fault energy and Cr and Si for the decrease.