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Real-time Internal Stress of Nickel Sulfamate Electroform  

Kim I. (Dept. of Materials and Metallurgical Engineering, Dong-eui University)
Kang K. (Dept. of Materials and Metallurgical Engineering, Dong-eui University)
Lee J. (Dept. of Materials and Metallurgical Engineering, Dong-eui University)
Kwon S.C. (Dept. of Surface Engineering, Korea Institute of Machinery & Materials)
Kim M. (Dept. of Surface Engineering, Korea Institute of Machinery & Materials)
Lee J.Y. (Dept. of Surface Engineering, Korea Institute of Machinery & Materials)
Publication Information
Journal of the Korean institute of surface engineering / v.38, no.1, 2005 , pp. 14-20 More about this Journal
Abstract
The control of internal stress is extremely important in electroforming because of the deliberately low adhesion between the electro form and the mandrel. Excessive tensile or compressive stress can cause distortion, separation problem, curling, peeling or separation of electroform prematurely from the mandrel, buckling and blistering. Nickel sulfamate bath has been widely used in electroforming because of its low internal stress and moderate hardness. In this study, real-time stress sensor has been used for stress control in chloride-free nickel sulfamate bath for 400 mm x 300 mm x 500 ㎛ nickel electroform. It was found that compressive stress found at low current density indicated the contamination of electrolyte, which is very useful in procuring buckling and peeling of electroform. No compressive stress is allowed for plate electroform. The real-time stress can also be used for accurate stress control of nickel electroform. The tensile stress was found to be increased slightly with increase in nickel electroform thickness, i.e., from initial 1.47 ksi to 2.02 ksi at 320 ㎛.
Keywords
Nickel sulfamate; Electroforming; Real-time stress sensor; Internal stress;
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  • Reference
1 G. Richardson, B. Stein, 1997 Electroforming Course & Symposium, San Diego, CA (1997)
2 S. C. Fawcett, D. Engelhaupt, Precision Engineering, 17 (1995) 290-297   DOI   ScienceOn
3 U.S. Patent 4,986,130 (1991)
4 R. Weil, 'The Origins of Stress in Electrodeposits', Plating, Part I, Dec. (1970) pp. 1231-1237. Part II, Jan. (1971) pp. 50-56. Part III, Feb. (1971) pp. 137-146
5 U.S. Patent 5,456,639 (1995)
6 L. E. Vaaler, R. D. Galliher, R. G. Brown, D. G. Rider, Plating and Surface Finishing, March (1988)
7 H. Feigenbaum, R. Weil, Plating and Surface Finishing, May (1979)
8 B. Stein, 'Fast and Accurate Deposit Internal Stress Determination' (1998) http://www.nicoform.com