TY  - CONF
A1  - Steppan, Enrico
T1  - Thermal desorption analysis of hydrogen trapping in micro-alloyed high strength steels
N2  - 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.
T2  - 69th IIW Annual Assembly and International Conference
CY  - Melbourne, Australia
DA  - 10.07.2016
KW  - Hydrogen embrittlement
KW  - Micro-alloyed high strength steels
KW  - Hydrogen trapping
KW  - Thermal desorption analysis (TDA)
KW  - S690
KW  - S700
KW  - Quenched and tempered
KW  - Thermo-mechanical
PY  - 2016
AN  - OPUS4-39459
LA  - eng
AD  - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER  -