Estudo de aços-ferramenta e de construção mecânica visando produção de ferramentas de alta resistência ao desgaste mecânico

Abstract

Tool and mechanical construction steels have diverse applications, from the manufacture of dies to cylinders. This study aimed to investigate these steels for the production of tools with high resistance to wear and abrasion. The research involved a bibliographical review of books, monographs, manuals and articles, as well as searches on websites specialized in heat treatments, aiming to determine the ideal thermal cycle for steels D2, D6, 1045 and 4340. After defining the thermal cycles, chemical composition tests were carried out on steel samples, provided by a metallurgical industry, at the UFC Materials Characterization and Welding Research Laboratories. These tests aimed to identify the chemical nature of the materials. Then, microstructural characterizations of the D2 and D6 steels were carried out, using a Zeiss optical microscope and a Scanning Electron Microscope from the UFC Analytical Center. The objective was to verify whether the microstructures of these steels met the standards established for annealed steels. The results showed that the D2 and D6 samples had elemental compositions within the designations X 155 CrVMo 12 1 e X 210 CrW 12, classifying them as tool steels for cold work, high carbon and high chromium, containing carbon and chromium carbides, with the addition of tungsten. Such microstructures are common in high chromium steels that have undergone annealing. Steels 1045 and 4340 presented chemical element contents within SAE standards, and are therefore classified as mechanical construction steels.