Accession Number:

ADD014040

Title:

Electrodeposition without Internal Deposit Stress.

Descriptive Note:

Patent, Filed 5 Jan 88, patented 22 Nov 88,

Corporate Author:

DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s):

• Vaaler, Luther E.

Report Date:

1988-11-22

Pagination or Media Count:

8.0

Abstract:

An apparatus and method are described for electrodepositing an electroform with near zero internal stress. A voltage controlled power supply supplies current to both a mandrel, upon which a primary electroform is deposited, and to a deformable thin disk substrate, upon which a secondary deposit is formed. A strain gage on the deformable substrate measures any deformation caused by internal stress in the secondary deposit. The strain gage is connected to a strain gage transducer to produce an output signal to a proportional controller. The proportional controller in turn supplies a strain-proportional voltage signal to the power supply. A current mask ensures an even current density over the mandrel. After initially adjusting electroforming bath parameters to provide a zero internal stress in the starting electroform, the output from the strain gage causes proportional changes in the bath current to the mandrel to maintain a constant near zero internal stress in the primary electroform. Patents. JES

Descriptors:

• *ELECTRODEPOSITION
• BATHS
• CONTROL
• CURRENT DENSITY
• DEFORMATION
• DEPOSITS
• DISKS
• ELECTROFORMING
• INTERNAL
• MASKS
• OUTPUT
• PARAMETERS
• PATENTS
• POWER SUPPLIES
• SECONDARY
• SIGNALS
• STARTING
• STRAIN GAGES
• STRESSES
• SUBSTRATES
• THINNESS
• TRANSDUCERS

Subject Categories:

• Fabrication Metallurgy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE