39459 2016 eng lecture 0 -- -- -- Hydrogen can have an extreme degradation effects in steels, particularly concerning the mechanical properties. These effects can lead to hydrogen assisted cracking in micro-alloyed high strength steels during fabrication and/or operation in industrial applications. The Carrier Gas Hot Extraction method, which functionally combines a mass spectrometer with a Thermal Desorption Analysis process, was used for the detection of ultra-low diffusible hydrogen concentrations in the material specimens. The work shows the interaction between hydrogen and lattice defects in different micro-alloyed materials and HAZ. These steels were prepared in a quenched and tempered condition and in a thermo-mechanically rolled condition. The trapping characteristics of two steel grades, S690QL and S700MC, were studied with respect to the activation energy dependent on carbon content and micro-alloying elements such as Ti, Nb, Mo, Cr and V. The two steel grades exhibited several types of traps: carbide formations, dislocations and/or grain boundaries were common, which can influence activation energy and hydrogen solubility. The type and dimension of inclusions or particles also affected the hydrogen trapping behavior. A decrease of carbon and specific alloying elements in MC steels led to a change in the activation energy binding the trapped hydrogen. This thermo-mechanically hot rolled steel revealed an increased interaction between hydrogen and precipitations. The higher carbon content in the quenched and tempered steel led to a higher interaction between hydrogen and iron carbide, specifically in the martensitic phase. Furthermore,the trapping behavior in HAZ showed a significant increase in activation energy, especially in the coarse grained microstructure. 69th IIW Annual Assembly and International Conference Melbourne, Australia 10.07.2016 15.07.2016 0 Enrico Steppan eng uncontrolled Hydrogen embrittlement eng uncontrolled Micro-alloyed high strength steels eng uncontrolled Hydrogen trapping eng uncontrolled Thermal desorption analysis (TDA) eng uncontrolled S690 eng uncontrolled S700 eng uncontrolled Quenched and tempered deu uncontrolled Thermo-mechanical Ingenieurwissenschaften und zugeordnete Tätigkeiten Datei im Netzwerk der BAM verfügbar ("Closed Access") Präsentation