Diggin, Myron B.
Vice President-Technical Director, Hanson-Van Winkle-Munning Co., Matawan, N. J.
Pages: 22 Published: Jan 1962
The criteria for the choice of an electrolyte for producing electroforms are: (1) physical, mechanical, and chemical properties required for each specific application, (2) permissible rate of deposition, (3) stability of the electrolyte and ease of management and control, and (4) costs in comparison with conventional fabrication methods. Properties of the deposits for various applications dictate the type of metal or alloy selected, the specific electrolyte to be employed, and the operating conditions of the bath. Significant physical, mechanical, and chemical properties of the resulting electroform which must be considered are: 1. Hardness—for wear and erosion resistance. 2. Internal stress—high internal stress, either tensile or compressive, may cause cracking, distortion, spontaneous wrinkling, or peeling from the matrix or mandrel. 3. Ductility—a brittle electroform is useless. 4. Electrical conductivity—an important factor in certain electroforms used in electronics and space vehicle components. 5. Thermal conductivity—especially important in producing plastic molds when rapid heating and cooling cycles are employed. 6. Corrosion resistance to environment—chemicals, heat, moisture. 7. Coefficient of friction—important where the electroform is used as a moving part against other surfaces. 8. Performance at extremely high or low temperatures. Some of the properties listed above do not have any significance for certain applications but usually several must fall within a predetermined range.
Paper ID: STP46001S