|GAUDE-FUGAROLAS Daniel||Independent Research in Physical Metallurgy and Engineering|
Several methods are used in industry to deal with the excess of dissolved hydrogen in metal aloys. Strict control on disolved hydrogen is necessary to reduce the risk of metal embrittlement and severe property loss. Composition and microstructure selection, vacuum casting, imposed thermal gradient diffusion and baking are some of the possible methods to reduce the risk of embrittlement. Each of these methods have its advantages and disavantages. One of hydrogen embrittlement mitigation methods most widely used in the steel industry consists in storing the metal parts in heated ovens for a long period of time, in a process known as baking, intended to promote the diffusion of hydrogen out of solution and into the atmosphere. By modelling the fluxes of hydrogen and its redistribution into various microstructure features it is possible to explain why this standard method presents varying degrees of success. This variability is related to the alloy microstructure and cooling process, which in turn influence where in the microstructure hydrogen is stored at the time of the treatment.