Project/Area Number |
26870058
|
Research Category |
Grant-in-Aid for Young Scientists (B)
|
Allocation Type | Multi-year Fund |
Research Field |
Physical properties of metals/Metal-base materials
Nanomaterials engineering
|
Research Institution | Nagano National College of Technology (2015) Tohoku University (2014) |
Principal Investigator |
YAGINUMA Shin 長野工業高等専門学校, その他部局等, 講師 (80516518)
|
Project Period (FY) |
2014-04-01 – 2016-03-31
|
Project Status |
Completed (Fiscal Year 2015)
|
Budget Amount *help |
¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000)
Fiscal Year 2015: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
Fiscal Year 2014: ¥3,120,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥720,000)
|
Keywords | アモルファス合金 / ナノワイヤー / ガスアトマイズ / 触媒 |
Outline of Final Research Achievements |
We have studied the formation mechanism of Pd-based metallic glass wires and droplets in the gas atomization process. The diameters can be reached to nanoscale and strongly related to the viscosity of molten alloys. We demonstrate that the numbers of droplets and wires can be distinguished by the Ohnesorge number (Oh), which is the proportion of the time scale of spinnability to that of capillary instability. The diameter distributions follow the log-normal distribution function that indicates cascade fragmentation. The median diameter is employed for evaluation criteria in the product diameter. For droplets, the number significantly increases at Oh < 1 but the diameter gradually decreases. For wires, the number greatly decreases at Oh < 1 while the diameter steadies below 400 nm. Further, the wire diameter is quadrupled at Oh = 16 due to the high viscosity which suppresses both capillary breakup and ligament elongation.
|