| Project/Area Number |
09650793
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Material processing/treatments
|
|---|
| Research Institution | Himeji Institute of Technology |
|---|
Principal Investigator |
YAMASAKI Tohru Himeji Institute of Technology, Department of Materials Science & Engineering, Associate Professor, 工学部, 助教授 (30137252)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
OGINO Yoshikiyo Himeji Institute of Technology, Professor Emeritus, 名誉教授 (10047574)
|
|---|
| Project Period (FY) |
1997 – 2000
|
| Project Status |
Completed (Fiscal Year 2000)
|
| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2000: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1999: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1998: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1997: ¥1,400,000 (Direct Cost: ¥1,400,000)
|
|---|
| Keywords | Electrodeposition / Ni-W Alloys / Amorphous / Nanocrystalline / Mechanical Properties / アモルファス合金 / Fe-W合金 / マイクロ部品用材料 / 硬度 |
|---|
| Research Abstract |
High-strength nanocrystalline Ni-W alloys were produced by electrodeoisition. The plating bath for the electrodeposition contained nickel sulfate, trisodium citrate, sodium tungstate and ammonium chloride, and was operated at various bath concentrations and conditions of electrolysis. The ductility and tensile strength of the deposited alloys are strongly influenced by inclusion of codeposited hydrogen during deposition process. After degassing the hydrogen, the high-strength nanocrystalline Ni-W alloy containing about 20.7 at.% W with an average grain size of about 3 nm has been obtained : the tensile strength attained to about 2300 MPa. The high ductility of this alloy was also observed : bending through an angle of 180 degree was possible without breaking. On annealing these materials at various temperatures, however, grain growth occurred and they lost their ductility. In order to estimate the critical grain size for keeping the good ductility in the nanocrystalline alloys, grain boundary sliding is considered to occur along the close-packed planes of the nanocrystalline grains under the condition where the nanoscaled spherical hard grains is represented as a densely packed array.
|
