A influência dos tratamentos térmicos na microestrutura e propriedades mecânicas do aço 1045

Abstract

The changes that contribute to the evolution of societies are linked to the capacity of human beings to produce and modify materials to meet their needs. In addition, it has been discovered that the properties of a material can be altered by means of heat treatments and addition of other substances. The progress of many of the technologies that make our existence so enjoyable is the exclusivity of the world that involves the study of materials. In this work the effects of the microstructure on the mechanical properties of the ABNT 1045 steel were studied under the different thermal treatments with the objective of forming several microstructures with different volumetric fractions of the ferrite, bainite, martensite and martensite phases with the intention of To relate them to the mechanical properties such as: yield stress, maximum stress supported by the material, ductility, hardness, energy absorbed by impact, among others. As a result, the heterogeneous microstructure of the steel before the heat treatments, the homogenization and the obtaining of the coarse perlite obtained in the full annealing, the fine pearlite observed after the normalization and the martensitic microstructure after the tempering and the martensite after the tempering were observed. Thus, these microstructures directly influenced the lower flow stress of the annealed steel compared to the normalized one, in the lower energy absorption by impact of 58.4J while the normalized one presents 73.4J and finally in the rockwell hardness C which presented higher value for the microstructure Tempered 63HRC and lower value for the annealed microstructure 14.1 HRC