Hydrogen embrittlement, an environmentally assisted form of corrosion, canbe considered as one of the most dangerous phenomena affecting mechanicalproperties of the metals, able to produce either a loss of ductility ortime-delayed fractures, even without any externally applied stress.Presently this phenomenon is not completely understood and hydrogenembrittlement detection, in particular, seems to be one of the mostdifficult aspects of the problem. The aim of this study was to verify thehydrogen embrittlement detection capability offered by the XRD ResidualStress Determination Technique. For this scope, steel AISI 4130 samples werehydrogen charged and their superficial residual stress was measured beforeand after the charging process. The results showed a lowering of thecompressive stress for the hydrogen charged samples, with a surfacecompression decrease proportional to the strength of the hydrogen chargingtreatment and in agreement with the hydrogen embrittlement expected effect.The reliability of this new ND technique was also compared withmetallographic inspection, mechanical tests and electronic microscopy.
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