Abstract
In this work the effect of the temperature on the growth of the shortness cracks and consequently on the mechanical properties of a 20Mn4 steel was studied. Uniaxial tensile tests were carried out on the thermo-mechanical simulator Gleeble 3800™ in a range of temperatures between 1000° and 1280°C. Heat treatments at different temperatures and holding times were performed in a tubular furnace.
After the tensile test and the heat treatments, the samples were characterised by secondary electron microscopy in order to evaluate the effect of microstructural evolution on the hot shortness behaviour. The copper agglomeration at the metal/scale interface is mainly responsible for the hot shortness phenomenon: for a characteristic range of temperature, a copper enriched liquid phase penetrates along grain boundaries promoting crack formation and hot shortness behaviour.
Keywords
Steel, heat treatments, hot-shortness, mechanical properties, microstructural evolution.
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