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Title: Annual Report Electrochemical Machining of Access Holes

Abstract

We report the advances made in electrochemical machining of access holes through sheet metal during FY2005. The cutting tool underwent a major engineering re-design to accommodate an oblong cut with parallel sides (1.5'' spacing) on a surface of arbitrary curvature. The solid cathode was replaced by an array of separately movable steel pins, allowing the tool to conform to the surface shape of the work piece prior to beginning cutting. Preliminary cuts through a hardened steel drum (0.04 inch thickness) were successfully completed at a low current (50A) but the current efficiency of the cutting process was poor (<30%). Efficiency was improved to 75% and the cutting time reduced to 8 minutes in heated electrolyte at 100 A and 4.5 V. This work led to improvements in process simplicity and ease of operation: (1) continuous movement of the cathode towards the work piece was eliminated in favor of a fixed cathode; (2) the surfaces of the cutting pins do not require insulation; (3) a spider support for the tool provides for rapid positioning of the cutting tool; (4) negative electrolyte pressure minimized leakage into the drum following breakthrough. We found no reactivity of various HE's with alternative candidate ECM electrolytes.

Authors:
; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
881665
Report Number(s):
UCRL-TR-218350
TRN: US200613%%142
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CATHODES; CUTTING TOOLS; EFFICIENCY; ELECTROCHEMICAL MACHINING; ELECTROLYTES; POSITIONING; SHAPE; SPIDERS; STEELS; THICKNESS

Citation Formats

Cooper, J F, Evans, M, and Whipple, R. Annual Report Electrochemical Machining of Access Holes. United States: N. p., 2006. Web. doi:10.2172/881665.
Cooper, J F, Evans, M, & Whipple, R. Annual Report Electrochemical Machining of Access Holes. United States. doi:10.2172/881665.
Cooper, J F, Evans, M, and Whipple, R. Wed . "Annual Report Electrochemical Machining of Access Holes". United States. doi:10.2172/881665. https://www.osti.gov/servlets/purl/881665.
@article{osti_881665,
title = {Annual Report Electrochemical Machining of Access Holes},
author = {Cooper, J F and Evans, M and Whipple, R},
abstractNote = {We report the advances made in electrochemical machining of access holes through sheet metal during FY2005. The cutting tool underwent a major engineering re-design to accommodate an oblong cut with parallel sides (1.5'' spacing) on a surface of arbitrary curvature. The solid cathode was replaced by an array of separately movable steel pins, allowing the tool to conform to the surface shape of the work piece prior to beginning cutting. Preliminary cuts through a hardened steel drum (0.04 inch thickness) were successfully completed at a low current (50A) but the current efficiency of the cutting process was poor (<30%). Efficiency was improved to 75% and the cutting time reduced to 8 minutes in heated electrolyte at 100 A and 4.5 V. This work led to improvements in process simplicity and ease of operation: (1) continuous movement of the cathode towards the work piece was eliminated in favor of a fixed cathode; (2) the surfaces of the cutting pins do not require insulation; (3) a spider support for the tool provides for rapid positioning of the cutting tool; (4) negative electrolyte pressure minimized leakage into the drum following breakthrough. We found no reactivity of various HE's with alternative candidate ECM electrolytes.},
doi = {10.2172/881665},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Jan 04 00:00:00 EST 2006},
month = {Wed Jan 04 00:00:00 EST 2006}
}

Technical Report:

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  • Housings for electromechanical switches often require deep noncircular shapes in hard-to-machine materials. In a study to determine if electrochemical machining (ECM) could increase production, it was found that ECM was twice as fast as conventional broaching. ECM was able to maintain tolerances of +-152 ..mu..m (0.006 in.) on surfaces and +-304 ..mu..m (0.012 in.) on fillet radii. These are three times and six times respectively less consistent than conventional broaching.
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