Abstract
The effects of anisotropy on the effective hydrogen diffusivity (Deff) and fatigue crack propagation (FCP) in a banded ferrite/pearlite AISI 4130 steel have been evaluated. Electrochemical permeation experiments indicate that the effective hydrogen diffusivity along the longitudinal (L) direction was higher than that along the transverse (T) direction, which in turn was higher than that along the through-surface (S) direction. These results can be applied to explain the hydrogen assisted FCP behavior of the banded structure successfully. When fatigue-tested in air, the FCP rate was similar regardless of the orientations. With hydrogen charging and for specimens that hydrogen can easily diffuse along L direction into the specimens, the FCP rate was the highest. In the case of specimens where hydrogen entry along S direction, the hydrogen diffusivity was the lowest, hence resulting in the lowest FCP rate in these specimens. Some specimens with a random ferrite/pearlite structure have also been included in the fatigue test as a control, so that the effect of inclusions can be separated from the banding effect.
| Original language | English |
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| Pages | 475-485 |
| Number of pages | 11 |
| State | Published - 1996 |
| Event | Proceedings of the 1994 5th International Conference on the Effect of Hydrogen on the Behavior of Materials - Moran, WY, USA Duration: 11 Sep 1994 → 14 Sep 1994 |
Conference
| Conference | Proceedings of the 1994 5th International Conference on the Effect of Hydrogen on the Behavior of Materials |
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| City | Moran, WY, USA |
| Period | 11/09/94 → 14/09/94 |