Hydrogen-induced ductility loss in ductile cast iron (DCI) was studied by conducting a series of tensile tests with three different crosshead speeds. By utilizing the thermal desorption spectroscopy and the hydrogen microprint technique, it was found that most of the solute hydrogen was diffusive and mainly segregated at the graphite, graphite/matrix interface zone and the cementite of pearlite in the matrix. The fracture process of the non-charged specimen was dominated by the ductile dimple fracture, whereas that of the hydrogen-charged specimen became less ductile by accompanying the interconnecting cracks between the adjacent graphite nodules. Inside of the hydrogen-charged specimen, the interspaces generated by the interfacial debonding between graphite and matrix are filled with hydrogen gas in the early stage of the fracture process. In the subsequent fracture process, such a local hydrogen gas atmosphere coupled with a stress-induced diffusion attracts hydrogen to the crack tip, which results in a time-dependent ductility loss.
|出版物ステータス||出版済み - 1 1 2013|
|イベント||13th International Conference on Fracture 2013, ICF 2013 - Beijing, 中国|
継続期間: 6 16 2013 → 6 21 2013
|その他||13th International Conference on Fracture 2013, ICF 2013|
|期間||6/16/13 → 6/21/13|
All Science Journal Classification (ASJC) codes
- Geotechnical Engineering and Engineering Geology