Mechano-thermal treatment of TiO2-Al powder mixture to prepare TiAl/Al2O3 composite

Abstract

In this research, a composite comprising an intermetallic matrix and dispersed Al2O3 particles was processed. A mixture of TiO2 and Al was mechanically activated in the presence of a process control agent and/or without it, in a high-energy planetary ball mill. As a subsequent process, the sample was sintered at various temperatures. The phase composition and morphology of the samples were evaluated by XRD and SEM techniques, respectively. The thermal behavior of the samples milled for 8 h with PVA and/or without it, were also assessed by the DTA technique and compared with one another. The DTA results revealed that addition of PVA shifted the aluminothermic reduction of TiO2 to higher temperatures; therefore, final composite phases were developed at higher temperatures. The results also showed that addition of PVA during milling caused the final microstructure to coarsen. The XRD pattern of the sample sintered at 700°C exhibits the existence of TiAl, Ti3Al, and Al2O3 phases. In the sample sintered at 850°C, the remaining Ti3Al peak was attenuated and completely disappeared at 1000°C.

Workability studies on Al+2.5%TiO2+Gr powder metallurgy composites during cold upsetting

“…Even though Titanium dioxide (TiO 2 ) possesses high hardness and modulus with superior corrosion resistance and wear resistance, it is not concentrated much by the recent researchers 17 . Al-TiO 2 composite system is one of the interesting material systems, and it has been produced by vortex casting and squeeze casting process and its properties are reported 18 . Also Somaye Alamolhoda et al produced TiAl/Al 2 O 3 composite from Al-TiO 2 powder mixtures using high-energy planetary ball mill through mechanical activation mechanism 19 .…”