TopicS: Structural Materials
A severe reduction of fracture resistance has been observed frequently due to the hydrogen penetration into alloys. For more than a century, scientists and engineers are working on hydrogen-induced degradation in materials and this topic remains important from the scientific and industrial points of views. Three main driving forces for research and development in hydrogen related topics are: i) progress in the characterization techniques; ii) recent materials development; which is about production of high strength alloys containing more complex microstructure which are more sensitive to environmental degradation, and iii) the glorious perspectives of hydrogen energy and fuel cell technology; while pressurized gaseous hydrogen is still the best option for the vehicles. Hence, the risk assessment of the tanks is an important issue. Since now, a variety of techniques (e.g. conventional testing methods, such as tensile and compression tests in conjunction with ex-situ or in-situ hydrogen charging and post mortem fractographic of the samples) were used to develop models for explaining the hydrogen assisted mechanical degradation. For a more fundamental understanding of the contribution of hydrogen on deformation behavior of alloys, crack initiation and its propagation mechanisms, local testing methods were performed using in-situ SEM, TEM and nanoindentation. Moreover, there are huge advances regarding the local measurement of the hydrogen content (e.g. by using SKPFM). The resolution of the more conventional techniques (e.g. SIMS and TDS) was also improved. Another progress in this field is using atomic scale, micro and macro scale simulations. Static and molecular dynamics (MD) simulations based on density functional theory (DFT) are used to evaluate how H affects the GB structure and the chemical bonds. This information could be integrated in macroscopic models (e.g. FEM).
To address the most important subjects related to hydrogen, we plan to cover the five following topics in our symposium.
- H-Enhanced deformation and fracture, conventional experimental approaches;
- Modelling the local and global impact of hydrogen on the mechanical properties;
- Advanced Methods for local hydrogen detection and characterization of Hydrogen-Materials Interactions.
- Hydrogen degradation of non-metallic materials
- Challenges and perspectives of hydrogen energy and Fuel Cell Vehicles.