Modification of properties of Ti-Al intermetallic phases by introducing TiB2 particles

Aim of project
The ordered intermetallic phases, especially from the Ti-Al system, have been of great interest for scientists for many years. So far, they have been one of the most developing groups of high-temperature construction materials and in comparison to titanium alloys, they have much greater elasticity, smaller density, greater strength and corrosion resistance at high temperatures. In order to use their potential fully, however, the following properties need to be improved: fl ow resistance, dynamic strain and resistance to brittle cracking at low temperatures. Most steps taken to improve these properties concentrate on adding certain elements to intermetallic phases and heat treatment in order to obtain the appropriate microstructure.

An alternative method of improving the properties of intermetallic phases can be creating composites on their matrix. The basic aim of this project is modification of mechanical properties (HV, KIC) and heat resistance of intermetallic phases TiAl (α2+γ) by introducing TiB2 ceramic particles.

Expected results
The final result will be a characterization of the following properties of TiAl (α2+γ)/TiB2 composites with variable weight ratio of ceramic phases — from 0% to 15%:

resistance to brittle cracking K IC, hardness HV, elasticity modules E

resistance at higher temperatures

oxidation kinetics, morphology and chemical composition of the oxides layer

A material result of the research will be creation of technology fundamentals on modification of mechanical properties of intermetallic phases from the system Ti-Al (i.e. Ti3Al and TiAl) with titanium diboride (TiB2) and widening knowledge on mechanical properties of composites on the matrix of intermetallic phases plasticized with the ceramic phase.

The results will contribute to a Ph.D. thesis preparation.