Caracterização microestrutural dos aços 1020, 1045, 5160, 8620, após os determinados tipos de tratamentos térmicos de têmpera, revenimento, normalização e recozimento.

Abstract

In the metal mechanical industry, there are processes and procedures that are dependent on the heat treatments possible to change the properties of the material when using these materials, thus leaving them in ideal conditions for application. Carbon steels have several applications such as: the automotive sector, manufacturing of metal-mechanical tools, aerospace sector, nuclear sector, among others. This great attraction for such steels is due to the fact that they are low cost materials and widely used in the industrial environment. The SAE 1020, 1045, 5160 and 8620 steels in this work were chosen because they are of great value to the metal- mechanical market and because they satisfactorily fill the most common possible applications in the current world market in components that may suffer as possible heat treatment for their maintenance. This work aims to study the microstructural modifications of certain heat treatments in SAE 1020, 1045, 5160 and 8620 steels, which are widely used in the metal- mechanical industry. A metallographic characterization of the materials in their as received condition was used, then a comparative analysis was performed with the samples that were subjected to heat treatments of tempering, normalization and annealing, in a standardized temperature range of 850ºC, and a heat treatment of tempering, in a temperature of 600ºC. With the analysis of optical microscopy it was possible to perform a qualitative analysis of the phases present in all samples. Thus, it was concluded that the 1020, 1045, 5160 and 8620 steels are closely related to the expected constituents in their TTTs diagrams and that the temperature standardization of the heat treatments, in due project, became effective.