| Project/Area Number |
14550715
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Material processing/treatments
|
|---|
| Research Institution | TOYOTA TECHNOLOGICAL INSTITUTE |
|---|
Principal Investigator |
OKUMIYA Masahiro TOYOTA TECHNOLOGICAL INSTITUTE, School of Engineering, Associate Professor, 工学部, 助教授 (20177182)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
IMADA Yasuo TOYOTA TECHNOLOGICAL INSTITUTE, School of Engineering, Research Associate, 工学部, 助手 (90148354)
|
|---|
| Project Period (FY) |
2002 – 2003
|
| Project Status |
Completed (Fiscal Year 2003)
|
| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2003: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2002: ¥2,700,000 (Direct Cost: ¥2,700,000)
|
|---|
| Keywords | Ultrasonic Vibration / cBN / Electroless Ni-P Plating / deposition rate / adhesive strength / 無電解Ni-Pめっき / 微小硬さ試験機 / 交換電流密度 / 分極測定 |
|---|
| Research Abstract |
Electroless plated cBN abrasive wheels, which life is dependent on the grit adhesion and the projection height at the interface, have been applied to grind ferrous materials. This paper presents a novel process of fabrication of highly adhesive grits abrasive wheels by electroless composite plating with ultrasonic vibration to improve the wheel life. The ideal interface between cBN grits and Ni-P matrix is expected to be heaping-up morphology in the matrix side.
Electroless plating was carried out at 363 K for 15 ks with different vibrational amplitudes (X_a) of ultrasound. The deposition rate was estimated by measuring each deposit thickness. It increases, with X_a up to 11 μm, however, it decreases beyond X_a of 12μm. The maximum deposition rate at X_a of 11・ m is 1.6 times higher than that without ultrasound. An increase in the deposition rate is confirmed by an increase in the exchange current in polarization measurements, since the ultrasound promotes the separation of hydrogen babbles at the substrate surface and the supplies of Ni^<2+> H_2Po_2^-. In contrast, a decrease in the deposition rate is explained by the destruction of plated matrix due to cavitations.
The interfacial morphology was observed on surface prepared with and without ultrasound. The interface is a flat or slightly sink-shape in the case without ultrasonic vibration. On the contrary, it exhibits heaping-up morphology with applying ultrasound. The heaping-up height and width depend upon A, and become the maximum at X_a of 11 μm. With the best interfacial morphology, the adhesive strength becomes 20 % higher than that without applying ultrasound in the horizontal pushing away tests, this is also qualitatively confirmed in stress analysis of FEM. Hence, electroless plating process with ultrasonic vibration is effective for the fabrication of highly adhesive grits abrasive wheels, since the interface exhibits heaping-up morphology.
|
