Akademik Veri Yönetim Sistemi
International Pumice and Perlite Symposium, Bitlis, Türkiye, 4 - 06 Kasım 2021, ss.27
In thermal barrier applications, the surface exposed to high heat is usually made of ceramic and the other surface
is made of metal. The incompatibility in the thermal expansion coefficient between two materials causes cracks
on the surfaces where metal and ceramics meet, thus decreases in mechanical properties. For this reason,
functionally graded composite material (FGCM) approach has been put forward in order to make the transition
between metal and ceramic more harmonious. In this study, pumice was used as a reinforcement material in the
metal matrix composites (MMCs). Pumice is suitable for use in MMCs because of its very low density, high
hardness and high porosity, especially for thermal insulation applications. 0, 10, 20% pumice-Al6061 MMC and
a FGCM designed as three layers were produced with powder metallurgy method. Vickers hardness and
compression tests were carried out to determine the mechanical properties of MMCs and FGCM. According to the
results, it was understood that the 20% reinforced MMC was 28.1% and 242.7% harder than the 10% reinforced
and non-reinforced, respectively. The 20% reinforced MMC showed 564.5%, 26.8%, 396.4% higher yield strength
than unreinforced, 10% reinforced and FGCM, respectively. FGCM exhibited weaker yield strength compared to
10% and 20% reinforced, and higher yield strength compared to unreinforced Al6061. Finally, it was determined
that the ductility of the material decreased with the increase in the reinforcement ratio. However, it is also
noteworthy that the ductility of FGCM is higher than 10% and 20% reinforced composite.
Keywords: Al6061, Compression test, FGCM, Pumice, Vickers hardness