Addressing H-Material Interaction in Fast Diffusion Materials—A Feasibility Study on a Complex Phase Steel

Abstract

Hydrogen embrittlement (HE) is one of the main limitations in the use of advanced high-strength steels in the automotive industry. To have a better understanding of the interaction between hydrogen (H) and a complex phase steel, an in-situ method with plasma charging was applied in order to provide continuous H supply during mechanical testing in order to avoid H outgassing. For such fast-H diffusion materials, only direct observation during in-situ charging allows for addressing H effects on materials. Different plasma charging conditions were analysed, yet there was not a pronounced effect on the mechanical properties. The H concentration was calculated while using a simple analytical model as well as a simulation approach, resulting in consistent low H values, below the critical concentration to produce embrittlement. However, the dimple size decreased in the presence of H and, with increasing charging time, the crack propagation rate increased. The rate dependence of flow properties of the material was also investigated, proving that the material has no strain rate sensitivity, which confirmed that the crack propagation rate increased due to H effects. Even though the H concentration was low in the experiments that are presented here, different technological alternatives can be implemented in order to increase the maximum solute concentration.

Research on Carbide Characteristics and Their Influence on the Properties of Welding Joints for 2.25Cr1Mo0.25V Steel

“…This indicates that hydrogen has a more significant effect on the performance of WM than BM. This phenomenon of ductile loss after hydrogen charging is in agreement with the previous study [ 40 , 41 , 42 ].…”

Effect of Tensile Loading and Temperature on the Hydrogen Solubility of Steels at High Gas Pressure

“…[4] However, hydrogen absorption of ferritic and martensitic steels raises major concerns with regard to hydrogen embrittlement, which can reduce the lifetime of steel components by accelerating crack growth and fracture. [5][6][7] A mechanistic lifetime assessment is very difficult, as potential mechanisms of hydrogen embrittlement are not fully understood and thus extensively discussed. [8,9] Therefore, the qualification of structural materials with respect to their resistivity against hydrogen embrittlement mainly relies on experimental testing and standards.…”

The role of hydrogen diffusion, trapping and desorption in dual phase steels

“…Critical hydrogen sources are present during materials processing as well as during service [12,13]. Hydrogen can be absorbed at the surface, resulting in an inhomogenous hydrogen distribution [14][15][16][17] in the steels, which is strongly influenced by plastic deformation [18], residual stresses and edge conditions [19][20][21][22]. Hydrogen desorption at room temperature is a crucial problem during testing of hydrogen embrittlement [23], which makes determining the hydrogen embrittlement threshold for a given hydrogen content difficult.…”