EFEITO DA TAXA DE RESFRIAMENTO NA OCORRÊNCIA DE AUSTENITA RETIDA EM UM AÇO PARA ELETRODOS DE SOLDA

The effect of cooling rate on the occurrence of retained austenite in a low carbon Si-Mn steel, used for welding\udelectrodes, is measured here by combining the sectioning of Jominy test samples with the measurement of retained austenite\udby X-ray diffraction. It was observed that the amount of retained austenite increases from zero, as the cooling rate is less\udthan 0.8°C/s, and the structure is mostly ferrite, to a maximum of 6%, where the quantity of bainite is also maximum.\udThis information guides the post-rolling cooling cycle when welding grade is been rolled. The hard phases proportionality\udwith the amount of retained austenite allows, then, the use of X-ray diffraction as an end of the line equipment for quality\udcontrol, and also permits simplification of heat treatment before wire drawing