About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
|
Symposium
|
Environmentally Assisted Cracking: Theory and Practice
|
Presentation Title |
Combined Ab-initio and Experimental Study of Hydrogen Sorption in Dual Phase Steels |
Author(s) |
Saurabh Sagar, Vera Popovich, Pascal Kömmelt, Poulumi Dey |
On-Site Speaker (Planned) |
Saurabh Sagar |
Abstract Scope |
Controlling the detrimental effect of hydrogen on the mechanical behaviour of AHSS is decisive for their application. A combined ab-initio- experimental approach was used to study the hydrogen sorption in two different DP800 steel grades using cyclic voltammetry and potentiostatic oxidation. Under the same charging conditions, diffusible hydrogen concentration was found to be higher in the vanadium grade as compared to the titanium grade. Scanning Electron Microscope characterisation revealed a more compact layer of oxide on the vanadium grade which contributed to more hydrogen absorption on the surface. Density Functional Theory calculations were performed to determine the trapping strength of precipitates of titanium and vanadium. Off-stoichiometric vanadium carbide was found to be the strongest trap, with carbon vacancies in the bulk of precipitates being favourable hydrogen trapping sites. Comparison of the DFT results with experiments suggested that the absorbed hydrogen could not reach the precipitates where it could get trapped. |
Proceedings Inclusion? |
Planned: |