Effect of particle size on the formation of Ti2AlC using combustion synthesis

Abstract

This paper provides an insight into the effect of particle size of elemental metal powders and carbon source on the formation mechanism of Ti 2 AlC MAX-phase ceramic produced by selfpropagating high-temperature synthesis (SHS). The effect of titanium, aluminium and carbon particle size on the 2Ti + Al + C → Ti 2 AlC reaction, the phase evolution of the final product and the porosity in both the green body and product has been examined. The effect of the carbon source in the form of graphite, carbon black and short carbon fibres on the reaction mechanism is explained. It is found that the particle size of the titanium and aluminium reactants had little effect on the phases formed but affected the green density of the reactants and the porosity in the final product. The carbon source used in the combustion reaction had an influence on the phases formed by the SHS reaction and was influenced by the dispersion of carbon particles and the titanium-aluminium particle contact.

The synthesis and mechanical properties of high pure Ti2Al(Sn)C solid solution

“…The synthesized aggregations were ball milled and then hot pressed (named two‐time hot‐pressing method, shorthand for two‐time HP in the following paper) to prepare fully dense Ti 2 AlC and Ti 2 Al 0.8 Sn 0.2 C bulks. Preparation methods of MAX bulks include Spark Plasma Sintering (SPS), in comparison with Self‐propagating High‐temperature Synthesis (SHS), HIP and two‐time HP . Two‐time HP is more convenient way to prepare single phase Ti 2 Al 1− x Sn x C ( x = 0‐1) solid solution bulks merited due to its low cost.…”

Low‐temperature synthesis of high‐purity Ti 2 AlC powder by microwave sintering

“…Various methods have been employed to synthesise bulk Ti 2 AlC samples although Ti 2 AlC was first synthesised and its structure was elucidated in the early 1960s [2]. However, it was very difficult to prepare phase‐pure Ti 2 AlC due to the narrow phase range in the Ti–Al–C ternary phase diagram [3, 4]. In the late 20th century, Barsoum et al [5, 6] successfully fabricated high‐purity Ti 2 AlC polycrystals by reactively hot‐pressing and high‐isostatic pressing a mixture of Ti, graphite and Al 4 C 3 powders.…”

Brazing mechanisms of the Ti 2 AlC joints using a pure Al filler metal

“…Such characteristics qualify the Ti 2 AlC ceramics for many structural and functional applications as, for example, the heat/electron exchanger or high temperature solid lubricant. Numerous efforts have been carried out to synthesize Ti 2 AlC ceramics, via various techniques like combustion synthesis (CS) [6], spark plasma sintering (SPS) [7] and self-propagating high-temperature synthesis (SHS) [8]. However, it is still difficult to process dense Ti 2 AlC ceramics with high purity, large dimensions and complex shapes, because of the narrow single Ti 2 AlC phase domain in the Al-C-Ti ternary phase system [9], which severely limits its applications.…”