Accession Number:

ADA180357

Title:

Acoustic Emission During Chromium Plating

Descriptive Note:

Final rept.

Corporate Author:

ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER WATERVLIET NY BENET WEAPONS LAB

Report Date:

1987-03-01

Pagination or Media Count:

25.0

Abstract:

The authors used acoustic emission to study crack formation during the electrodeposition of chromium over a range of temperatures and current densities which characterize the transition from high contraction HC to low contraction LC chromium. Several characteristics of the acoustic emissions were examined, including the amplitude distribution, signal energy, emission rate, count rate, and frequency spectrum. The acoustic emission technique detected the onset of cracking and yielded useful information regarding the number of cracks. Such information acquired during the actual deposition process can be an invaluable aid in determining the quality of the deposit and in developing improved chromium coatings. Experimental data were acquired and analyzed using commercial acoustic emission instrumentation, including standard piezoelectric transducers. The deposition bath was a standard aqueous solution of 250 gram per liter chromic acid and 2.5 gl sulfuric acid. The solution temperature and deposition current density were varied to obtain deposits of differing crack content. The substrate was electropolished carbon steel.

Subject Categories:

  • Fabrication Metallurgy
  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE