Institute of Physics of Materials AS CR, v. v. i. > Projects > Improvement of Properties and Complex Characterization of New Generation Fe-Al-O Based Oxide Precipitation Hardened Steels
Improvement of Properties and Complex Characterization of New Generation Fe-Al-O Based Oxide Precipitation Hardened Steels
| Investigator | RNDr. Jiří Svoboda, CSc., DSc. |
| Number of Project | 17-01641S |
| Agency | Grantová agentura České republiky |
| Duration | 2017-01-01 - 2019-12-30 |
Anotace |
| The applicants have developed new low-cost Fe-Al-O based Oxide Precipitation Hardened (OPH) ferritic steels, with excellent high temperature oxidation resistance and microstructure stability. The steel can be prepared in two steps: 1. mechanical alloying of Fe and Al powders in controlled O2 atmosphere, during which oxygen is trapped at multiple defects in the matrix and 2. hot consolidation by rolling, during which fine Al oxides precipitate from the supersaturated recrystallized matrix Fully dense fine-grained (100-200nm) steel with homogeneous dispersion of 2-5 vol.% of Al oxides (10-20nm) is hard and brittle, however, its hot forming is easy. During annealing above 1000°C abnormal grain growth leads to 50-100 mym grains by keeping the size of oxides unchanged and the steel gets softer and ductile. The new OPH steel exhibits very promising mechanical properties between room temperature and 1100°C. Several grades of the OPH steel will be prepared and complexly characterized from the point of mechanical properties, microstructure long-term stability and ability of hot forming. The project aims are improvement of OPH steels by varying milling and rolling conditions and oxygen content followed by evaluation. Complex characterization of improved grades with various oxygen content covering fracture, creep, fatigue and hot formability properties, microstructure stability and oxidation resistance. |
