Characterization of Process for Embedding SiC Fibers in Al 6061 O Matrix Through Ultrasonic Consolidation

Abstract

In this paper, continuous SiC fibers were embedded in an Al 6061 O matrix through ultrasonic consolidation at room temperature. The optimum embedding parameters were determined through peel tests and metallographic analysis. The influence of the embedded fiber volume fraction and base metal thickness on the interface bond strength was studied, and the fiber/matrix bond strength was tested through fiber pullout test. The results showed that embedding ≥0.8% volume fraction of SiC fiber in a 6061 O matrix could significantly increase and even its interfacial strength, but there is a threshold for embedded fiber volume fraction at specific parameters, over which the plastic flow and friction may be insufficient to have a strong bond at foil/foil interfaces between fibers. The study also showed that base metal thickness did not have significant influence on the interfacial strength with an exception of samples with a base metal thickness of 500 μm. Based on the results, it was proposed that microfriction at consolidation interfaces plays an important role for joint formation, and localized plastic flow around fibers is important to have fibers fully and safely embedded.