Characterization of short fatigue cracks at notches in SiC particulate aluminum composite
The initiation and growth of cracks emanating from blunt notches in 6061-Al alloy reinforced with 25% particulate SiC metal matrix composite was investigated. To elucidate the role of aging condition of the matrix on the fatigue behavior, the studies were carried out at T6 and overaged conditions. The results indicate that the initiation of fatigue cracks are insensitive to the notch severity and to the aging condition of the matrix. The overaging heat treatment resulted in slower fatigue crack growth rates. The failure of the SiC particles during the fatigue process is given as the reason for the both observed initiation and crack growth characteristics. It is also shown that the growth rate of short cracks emanating from blunt notches can be accurately described by an effective stress intensity factor range {Delta}K{sub eff}. This could provide an adequate engineering method for design against fatigue failure from various stress concentrations for this composite system.
- Research Organization:
- Ames Lab., Ames, IA (United States)
- Sponsoring Organization:
- DOE/ER
- DOE Contract Number:
- W-7405-ENG-82
- OSTI ID:
- 6596898
- Report Number(s):
- IS-M-645; CONF-891024-8; ON: DE90018043
- Resource Relation:
- Conference: The Metallurgical Society fall meeting: materials week, Indianapolis, IN (USA), 1-5 Oct 1989
- Country of Publication:
- United States
- Language:
- English
Similar Records
The influence of SiC particulates on fatigue crack propagation in a rapidly solidified Al-Fe-V-Si alloy
Mechanisms of growth by short fatigue cracks in notched and smooth specimens of Al-SiC composites