Age hardening response of an Al/TiC hot pressed multi-layered composite: Influence on corrosion

Abstract

In this study, Al–Cu-based three-layered metal matrix composites reinforced with TiC particles were produced successfully by a conventional hot pressing method under argon (Ar) atmosphere. To evaluate the effect of heat treatment, the composites were treated for 24 h at 530°C and then aged in an oil bath at 180°C for various aging periods. The multi-layered composite was characterized by SEM, EDS, XRD, and the Vickers microhardness test. It was concluded that the peak hardness for the multi-layered composite was observed, when the aging period was extended up to approximately 12 h. The hardness of the middle layer increased from approximately 140 to 291 HV within 12 h. The corrosion resistance of the composites decreased with increasing aging time and some preferential corrosion attack was detected in the composite layers. In addition, it was found that the pitting susceptibility of unaged composites was also higher than that of all the aged specimens.