Hydrogen uptake and its influence in selective laser melted austenitic stainless steel: A nanoindentation study

Hydrogen uptake and its influence in selective laser melted austenitic stainless steel: A nanoindentation study

Scripta Materialia

10.1016/j.scriptamat.2020.113718

http://dx.doi.org/10.1016/j.scriptamat.2020.113718

Jeong-Min Park, Yakai Zhao, Thomas Voisin, Dong-Hyun Lee, Shin-ichi Komazaki, Yoonseok Ko, Dong-Ik Kim, Jin-Yoo Suh, Heung Nam Han, Y. Morris Wang, Upadrasta Ramamurty, Jae-il Jang

12 January 2021

Park, J.-M., Zhao, Y., Voisin, T., Lee, D.-H., Komazaki, S., Ko, Y., Kim, D.-I., Suh, J.-Y., Han, H. N., Wang, Y. M., Ramamurty, U., Jang, J. (2021). Hydrogen uptake and its influence in selective laser melted austenitic stainless steel: A nanoindentation study. Scripta Materialia, 194, 113718. https://doi.org/10.1016/j.scriptamat.2020.113718

The effect of hydrogen (H) charging on the nanoindentation response of a selective laser melted (SLM) 316L austenitic stainless steel was investigated and compared with its conventionally manufactured (CM) counterpart. Results show that the hardness increment in the SLM samples due to H charging is relatively smaller. Thermal desorption spectroscopy analysis suggests that the charged SLM alloy has not only a smaller H content but a lower apparent H diffusivity in comparison to the CM alloy. This was attributed to the ultrafine solidification cell structure in the SLM alloy. Through the low-load nanoindentation experiments and forward-scattered electron imaging analysis, statistical distributions of the hardness of the cell walls and interiors were assessed. The cell walls, consisting of high-density dislocations with segregated elements, were relatively insensitive to H charging than the cell interiors. These results are discussed in terms of the apparent H solubility and diffusivity in the SLM alloy.

Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)

This research / project is supported by the A*STAR - Structural Metal Alloys Programme
Grant Reference no. : A18B1b0061

https://oar.a-star.edu.sg/communities-collections/articles/20880

1359-6462

Institute of Materials Research & Engineering