Abstract
Since the first implementation of the micro-cantilever studies for fracture mechanical purposes in 2005, it has been found a great development both experimentally and regarding its applications. Employing this method in Hydrogen embrittlement (HE) studies has provided an opportunity for micro/nano-resolved structural characterization of the Hydrogen-metal interaction. Interaction of H, in particular, with microstructural interfaces, has been a subject of numerous studies. In polycrystalline bulk materials which are normally used for HE studies, various parameters participate in the final results and make it complicated for the researcher to explore the role of individual interfaces like GBs in mechanical response. Besides, the difficulties in the repetition of the test and reproducibility of the results are a concern for single, bi-crystal and polycrystalline materials.
The in-situ micro-cantilever bending test is a promising reproducible method to for micro/nanoscale interfacial HE analysis. Various interfacial microstructures interactions with H have been investigated in our group. In this paper, a wide range of interfacial HE studies has been demonstrated to show the achievements of the in-situ micro-cantilever bending approach. The case studies which are presented here include: the role of a single grain boundary (GB) in HE of BCC (pure iron, steels) and FCC (pure Nickel, Nickel superalloy) materials, the interaction of dislocations-GB in BCC and FCC bi-crystals, the role of the GB type on the HE, the role of the precipitates on HE of high strength steels and nickel-superalloys as well as the study of different beneficial or detrimental interfacial segregation like carbides, Sulfur, Boron, and copper on the HE of various materials.
In this paper, the achievements of the micro-cantilever studies in comparison with other methods in the HE area would be investigated and the possible ways of its development regarding the methodology and also combining with other methods will be discussed. In addition, the experimental limitations, challenges, and possible errors of this approach would be explained in real case studies.