The interactive role of inclusions and SiC reinforcement on the high-cycle fatigue resistance of particle reinforced metal matrix composites

Autor: Nikhilesh Chawla, J. W. Jones, L. C. Davis, John E. Allison, C. Andres
Rok vydání: 2000
Předmět:
Zdroj: Metallurgical and Materials Transactions A. 31:951-957
ISSN: 1543-1940
1073-5623
DOI: 10.1007/s11661-000-0037-y
Popis: The effect of intermetallic inclusions on the fatigue crack initiation and growth in 2080 Al alloy and 2080/SiC p composites was investigated. Using surface replication, it was determined that, in the high-cycle fatigue region, life is dominated by the initiation process. It was also determined that the majority of initiation sites were associated with intermetallic inclusions. While 2080/SiC/20 p showed a definitive relationship between inclusion size and fatigue life, i.e., a higher inclusion size resulted in lower fatigue life, there was no correlation in 2080/SiC/30 p . This was attributed to more of the load being shared by the higher volume fraction of SiC particles and smaller average inclusion sizes in the latter composite. A conceptual model is proposed that accounts for these observations and qualitatively shows the effect of reinforcement on stress enhancement in near-surface inclusions.
Databáze: OpenAIRE