Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1574277 | Materials Science and Engineering: A | 2015 | 8 Pages |
Abstract
A low carbon ferritic steel was alloyed with Ti, Mo and Cu with the intention of achieving greater increment in strength by multiple precipitate strengthening. The steel is hot rolled and subjected to interrupted cooling to enable precipitation of Ti-Mo carbides and copper. Thermodynamic calculations were carried out to determine equilibrium phase fractions at different temperatures. Microstructure characterization using transmission electron microscopy and composition analysis revealed that the steel contains ~5Â nm size precipitates of (Ti,Mo)C. Precipitation kinetics calculations using MatCalc software showed that mainly body centered cubic copper precipitates of size <Â 5nm form under the cooling conditions in the present study. The steel has the high tensile strength of 853Â MPa and good ductility. The yield strength increases by 420Â MPa, which is more than that achieved in hot rolled low carbon ferritic steels with only copper precipitates or only carbide precipitates. The precipitation and strengthening contribution of copper and (Ti,Mo)C precipitates and their effect on the work hardening behavior is discussed.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
M.P. Phaniraj, Young-Min Shin, Joonho Lee, Nam Hoon Goo, Dong-Ik Kim, Jin-Yoo Suh, Woo-Sang Jung, Jae-Hyeok Shim, In-Suk Choi,