Microdamage in Sliding Contacts
Abstract
Studies based on subjecting a ball-on-flat test specimen configuration to small amounts of slip ( 0 to 5 micrometers) suggest a possible mechanism for the initiation of surface damage and wear. This study, which was limited to SAE 52100 steel, indicated that a significant number of transitions occurred in the initiation of the fretting process. These transitions, in order of severity, included initially mild oxidation, minimal surface damage, and a mild to severe wear process characterized by a pitted wear surface, tensile stress cracking and microcrack formation. An SEM analysis of the Hertzian contact region under load indicated a significant surface roughening was found to correspond approximately to the size of carbide particles. This suggests that carbides, due to their higher modulus, might protrude out of the surface under load and thus after surface morphology in the ball/flat contact region. This change in surface morphology in the contact area could explain all of the various types of surface damage observed in this study. Data suggests that accelerated wear could be explained on the assumption that carbide particles could work free of the surface under high surface stress conditions and that these freed particles could then accelerate wear by acting as an abrasive in the contact zone. Keywords include: Fretting, Wear, Tests, Friction, Metal, Carbon steel, and Microslip.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1987
- Accession Number
- ADA196790
Entities
People
- Paul J. Kennedy
Organizations
- Naval Air Warfare Center Warminster