Abstract
Tensile behavior and structure-property relationship of ferritic steels with nano-sized carbide dispersion were invesigated using Ti-added steel and Ti,Mo-added low carbon steels. By austenitizing followed by isothermal heat treatment at 700°C, polygonal ferrites containing very fine carbides of TiC and (Ti,Mo)C were obtained in the Ti-added and the Ti,Mo-added steels, respectively. The size of such carbides was finer in the Ti,Mo-added steel than in the Ti-added steel at the same isothermal holding. The results of tensile tests for these samples showed that the strength is higher as the carbide size is smaller. The structure-based strength calculation led to a good agreement with the experiments, when it was assumed that the Ashby-Orowan mechanism is dominant for precipitation strengthening of nano-sized alloy carbides. It was also suggested that a relatively large tensile ductility is related to enhanced recovery during the tensile deformation, accompanied with promotion of secondary slips or cross slips in a finer scale due to the nano-sized particles.
| Original language | English |
|---|---|
| Pages (from-to) | 212-221 |
| Number of pages | 10 |
| Journal | Isij International |
| Volume | 54 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - 2014 Feb 26 |
Keywords
- Ductility
- Interphase precipitation
- Low carbon steel
- Precipitation strengthening
- Work hardening
ASJC Scopus subject areas
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry