Per: julianna magalhães garcia (IME - INSTITUTO MILI), ana carolina accioly monteiro (instituto militar de engenharia), Andrey de moraes barcelos casanova (instituto militar de engenharia), iana costa carvalho (instituto militar de engenharia), luiz paulo brandao (instituto militar de engenharia)
Abstract:
In this study, the microstructure of AISI 310 steel, previously creep tested until rupture, was evaluated. In temperature and time conditions between 650 °C and 700 °C and 2 to 1,231 h, respectively. To evaluate the microstructural evolution, X-ray diffraction, optical and scanning electron microscopy and Vickers micro-hardness tests were performed. Carbide, sigma phase and laves phases have been observed, varying over time of exposure, as seen by the diffractogram peaks accompanied by microscopic visualization. Microhardness increases pursued by a decreasing, following the transformation of the sigma phase in the matrix, demonstrating good relationships between the rupture temperatures and times with the microstructure and ageing time of the material and, specially, with the laves phase to increase the creep resistance of the material, being, an important point to optimize its application and maintenance.