Mechanisms of Fatigue in Filament-Reinforced Metals.
Abstract
The mechanisms of low-cycle fatigue were studied in composites of aluminum reinforced with 34 vol. % of continuous beryllium filaments. Two series of composite specimens were tested, one series fabricated using as-drawn (rough surfaces) beryllium wire and another using electropolished (smooth surfaces) beryllium wire, to determine the effects of mechanical interlock at the filament-matrix interface on fatigue performance. Axial, strain-controlled fatigue tests were performed. The cyclic stress-strain curves were identical for the two series of composite specimens, while composites reinforced with as-drawn filaments exhibited longer fatigue lives than composites reinforced with electropolished filaments. This difference in fatigue lives between the two series of composites was attributed to the difference in the rate of crack growth parallel to filament-matrix interfaces. It was concluded that rough filament surfaces impede interfacial crack growth, and that interface conditions and the resistance of the matrix to crack growth are important considerations in the design of fatigue-resistant, filament-reinforced metals. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1970
- Accession Number
- AD0872137
Entities
People
- J. R. Hancock
Organizations
- MRIGlobal