| Project/Area Number |
13650760
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Structural/Functional materials
|
|---|
| Research Institution | Osaka University |
|---|
Principal Investigator |
NAKANO Takayoshi Osaka Univ., Grad. School of Engng., Associate Prof., 大学院・工学研究科, 助教授 (30243182)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
UMAKOSHI Yukichi Osaka Univ., Grad. School of Engng., Prof., 大学院・工学研究科, 教授 (00029216)
|
|---|
| Project Period (FY) |
2001 – 2002
|
| Project Status |
Completed (Fiscal Year 2002)
|
| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2002: ¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 2001: ¥1,800,000 (Direct Cost: ¥1,800,000)
|
|---|
| Keywords | Transition metal silicide / Lamellar structure / Single crystal / Deformation and fracture / Slip system / Variant / Continuity of strain / C11_b phase / シリサイド / ラメラー組織 / 破壊・変形 / C11b / C40 / C49 / 界面制御 / 複相シリサイド / 超高温耐熱材料 / 転位 / NbSi_2 / 界面 / 方向制御層状組織 |
|---|
| Research Abstract |
Microstructures of duplex-phase C40/C11_b silicides from combinations of NbSi_2, Vsi_2 or TiSi_2 with MoSi_2 were investigated focusing on formation and alignment of lamellae. The lamellar structure was formed by zone melting and subsequent appropriate heat treatment for all combinations, but oriented lamellae were obtained only in NbSi_2 / MoSi_2 duplex crystals. The oriented lamellar structure satisfied the crystallographic relationship of (0001) _<C40> // (110) _<C11b>, < 1^^-21^^-0] _<C40> // [11^^-0] _<C11b> and < 101^^-0] _<C40> // [001] _<C11b>, resulting in formation of three variants of the C11_b phase and two kinds of boundary: a type of C11_b/C11_b grain boundary and a type of C11_b/C40 phase boundary. Further annealing induced coarsening of both phases and changed the crystallographic relation due to relaxation of misfit strain at boundaries.
|
