Accession Number : ADA953885

Title :   A Research Investigation of Possibilities for Obtaining Hot-Hard Electrodeposited Chromium or Chromium-Base Alloys for Cannon.

Descriptive Note : Interim technical rept. 17 May-30 Aug 49,


Personal Author(s) : Bride,J. E. ; Snavely,C. A. ; Faust,C. L.

Report Date : 30 AUG 1949

Pagination or Media Count : 45

Abstract : The objective of this research is to investigate possibilities for an erosion-resistant chromium or chromium-alloy electroplate for lining gun tubes. Chromium-iron alloy has been electrodeposited on short sections of 3' gun tube from the chrome-alum type bath at the rate of 0.010 per hour. The alloy is approximately 94% chromium and 6% iron. The grooves of the rifling were well covered with plate but the thickness in some areas was only about 1/10 that on the lands. The alloy has the favorable property of retaining its as-plated hardness of approximately 600 Knoop after heat treatment for 12 hours at 600C. It is essentially crack-free, but has less ductility than is desired for use in gun tubes. The effects of plating variables on the structure of the plate are shown in photomicrographs. Preliminary experiments have outlined favorable possibilities for the use of soluble alloy anodes to replace the insoluble anodes presently used.

Descriptors :   *Gun barrels, *Chromium, *Chromium alloys, *Electroplating, Ductility, Linings, Erosion resistance, Heat treatment, Electrodeposition, Hardness

Subject Categories : Metallurgy and Metallography
      Fabrication Metallurgy
      Fire Control and Bombing Systems

Distribution Statement : APPROVED FOR PUBLIC RELEASE