Production of Ti-Fe based MgAl2O4 composite material by pressureless infiltration method

Abstract

In spite of their high temperature and corrosion resistance, ceramics show a brittle nature under applied loads and this limits their usage areas. In order to compensate the weakness of ceramics with metals, which have high ductility, the production of ceramic-metal composite materials has been recently started. In the present study, a ceramic-metal composite material was produced by means of pressureless infiltration method using spinel oxide (MgAl2O4) and Ti-Fe alloy. Atmospheric conditions, Ti-Fe/MgAl2O4 ratio, infiltration temperature and time were chosen as an experimental parameter. The experimenral results showed that a passivating oxide layer on the surface of the Ti-Fe alloy was observed in ambient atmosphere at 1600 degrees C for 120 minutes and therefore no reaction took place between the spinel and Ti-Fe alloy. Whereas, the Ti-Fe alloy was successfully infiltrated under argon atmosphere at 1550 and 1600 degrees C for 30, 60 and 120 minutes. The infiltrated Ti-Fe composites were characterized using SEM equipped with EDS. The hardness values of the Ti-Fe/MgAl2O4 composite increased up to 22.5 % Ti-Fe amount and further increase in the Ti-Fe amount led to a decrease in the hardness.