Cracking the Initiation Mechanism of High Cu-Bearing Nitrogen-Alloyed Austenitic Stainless Steel in the Process of Hot Deformation
| Autor: | Pu-cun Bai, Xiao-yang Fu, Ji-chun Yang |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
lcsh:TN1-997
Materials science Energy-dispersive X-ray spectroscopy crack 02 engineering and technology engineering.material 01 natural sciences austenitic stainless steel law.invention hot deformation Optical microscope law 0103 physical sciences General Materials Science Austenitic stainless steel Composite material lcsh:Mining engineering. Metallurgy Stress concentration 010302 applied physics Cu-bearing Metals and Alloys nitrogen-alloyed 021001 nanoscience & nanotechnology Microstructure Transmission electron microscopy engineering Grain boundary Deformation (engineering) 0210 nano-technology |
| Zdroj: | Metals Volume 8 Issue 10 Metals, Vol 8, Iss 10, p 816 (2018) |
| ISSN: | 2075-4701 |
| DOI: | 10.3390/met8100816 |
| Popis: | The cracking initiation mechanism of high Cu-bearing nitrogen-alloyed austenitic stainless steel was systematically investigated by using a Gleeble-1500D simulator under different strains and deformation temperatures in the hot deformation process. The cracking initiation process and microstructure variations were characterized by optical microscopy (OM), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) with energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). In the deformation process, Cu-rich and Cr-rich phases were found around the microscopic crack at the strain of 0.5. Cu content was found to be higher at the grain boundary than inside the grain. The equilibrium phase diagram calculated by Thermo-calc shows that Cu precipitates out in the form of an elementary substance below 1022 ° C, when the Cu mass fraction reaches 5%. Meanwhile, dislocation walls and twin crystals were observed by TEM. The results show that the synergistic effect of the secondary phases, such as M23C6 precipitated along the grain boundary and stress concentration, lead to crack generation, which is lower at high temperature and low temperature and is higher at 1100 ° C and increase as the strain increases. |
| Databáze: | OpenAIRE |
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