Effect of sonication on the electroless Ni-B deposited powder from acid bath.
The electroless deposition rate of Ni-B powder increased with sonication (ultrasonic agitation). The boron content in deposited amorphous powder was about 2.2% with and without sonication. When Ni(II) ion was 20.0 mol/dm(3), deposition efficiency was 65% in 14 mmol/dm(3) dimethylamine boran (DMAB) and 90.2% of Ni(II) ion deposited over 33.9 mmol/dm(3) DMAB adding 100 mg/dm(3) powder. When DMAB ion was 1.7 times of Ni(II) ion, deposition efficiency was 90.2% over 20.0 mmol/dm(3) Ni(II) ion adding 100 mg/dm(3) powder. The optimum ratio of Ni(II) ion and DMAB concentration was 1:1.7. Deposition efficiency was larger about two times compared with that of the stationary state. The powder was amorphous. The particle form was spherical. Particle size of 0.75-1.25 microm was about 40%, and that of 1.25-1.75 microm was about 25%. Crystals of amorphous powder formed by heating from 573 to 773 K.
Chiba
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Department of Materials Chemistry, Faculty of Engineering, Yokohama National University, 79-5, Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan. a-chiba@ynu.ac.jp
Haijima
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Wu
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