Quantification of the temperature threshold of hydrogen embrittlement in X90 pipeline steel
Autor: | Chao Yang, Ran Cheng, Jianguo Liu, Zili Li, Feng Yang, Gan Cui, Xiao Xing, Jinxin Gou |
---|---|
Rok vydání: | 2021 |
Předmět: |
010302 applied physics
Materials science Structural material Hydrogen Scanning electron microscope Mechanical Engineering Diffusion Thermodynamics chemistry.chemical_element 02 engineering and technology Strain rate 021001 nanoscience & nanotechnology Condensed Matter Physics Thermal diffusivity 01 natural sciences Molecular dynamics chemistry Mechanics of Materials 0103 physical sciences General Materials Science 0210 nano-technology Hydrogen embrittlement |
Zdroj: | Materials Science and Engineering: A. 800:140118 |
ISSN: | 0921-5093 |
DOI: | 10.1016/j.msea.2020.140118 |
Popis: | In the current research, the dependence of hydrogen embrittlement (HE) on the temperature in X90 steel is studied through experimental tests and molecular dynamics simulations. Slow strain rate tests (SSRT) were applied to X90 specimens in the air and the simulated groundwater solution (called NS4), respectively. The fracture morphologies of the specimens were observed by scanning electron microscope (SEM). The results indicate that the temperature threshold of hydrogen embrittlement (HE) in X90 steel is 313 K, beyond which the HE would be weakened with the rise of temperature, and below which the HE would be enhanced with the rise of temperature. To illustrate the underlying mechanism of this phenomenon, molecular dynamics simulations were applied to quantify the correlation of temperature with hydrogen diffusivity, and the results of Devanathan-Stachurski tests were used to quantify the bulk hydrogen concentration at different temperatures. A theoretical model was thus developed based on hydrogen potential thermodynamics to predict the threshold temperature. The predictive model matches well with experimental results, revealing the promoting effect of hydrogen diffusion and accumulation on the crack growth, which is fundamental for understanding hydrogen-induced damage in structural materials. |
Databáze: | OpenAIRE |
Externí odkaz: |