Accession Number:

AD0725011

Title:

Selection of Materials for Parts Operating Under Bearing Contact and Erosion-Corrosion Wear Conditions,

Descriptive Note:

Technical Report

Corporate Author:

FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OH

Report Date:

1971-01-13

Pagination or Media Count:

14.0

Abstract:

The effects of the simulataneous actions of erosion and friction on the wear of 4 kinds of cast-iron containing Cr 12.40-14.05 and C 1.15-1.71 wt percent were studied. Two of these cast irons were inoculated. The friction deformation of some of the cast irons had a large accelerating effect on the corrosion resistance. For instance, the corrosion rate of 2 cast irons during friction in a condensate medium without preliminary friction deformation, was 0. 0336 and 0.0292 mmyear, resp., while after deformation, the corrosion rate at similar conditions 0.056 and 0.0196 mmyear, resp. This difference is assumed to be the result of considerable changes in the structure of the surface layer. During friction deformation as the result of increased temp., phase and allotropic transformations took place to the depth of 45-60 mu, with the formation of austenite. Although austenite is more corrosion resistant than ferrite, vol. changes during the transformation resulted in the formation of fissures with resulting acceleration of corrosion disintegration. Cr, Mo, and W diffuse inward from the surface layer during the friction deformation and this also accelerates the erosion rate. For proper evaluation of the wear, the materials should be tested by exposure. Author

Subject Categories:

  • Properties of Metals and Alloys

Distribution Statement:

APPROVED FOR PUBLIC RELEASE