| 研究実績の概要 |
The subject of this year was focused on the effects of deformation conditions of CRB on the microstructure and mechanical properties.
1)The results of brass tube showed that the microstructure was successfully refined and the plasticity of brass tube were improved through adjusting the experimental conditions. The average grain size decreased with the increase of rotation time at RT. With the same rotation time of 5 min, the grain size increased with the deformation temperature increased from 100 °C to 300 °C. The CRB process also shows a significant influence on the mechanical properties of brass tube. In the CRB processes carried out at RT, the strength decreased and the plasticity increased when the rotation time increased from 2 min to 8 min. With the same rotation time of 5 min, the strength decreased, and the plasticity increase first and then decreased with the deformation temperature increased from 100 °C to 300 °C.
2)The results of steel tube showed that the grains were successfully refined by CRB which were carried out at 600°C, 700°C and 800°C. The reduction rate of grain size decreased with the increase of temperature from 600°C to 800°C. The mechanical properties were also improved by the CRB process.
3)To study relationships between the grain size and the accumulated equivalent strain, the FEM simulation of CRB processes was also carried out. The calculated results of equivalent strain were used to verify the availability of FEM model. The deformation behavior and the status of strain as well as stress of metal tubes in CRB process were also obtained.
|
