Microstructure and Mechanical Properties of L1<SUB>2</SUB>-(Al, Cr)<SUB>3</SUB>Ti/Ti<SUB>2</SUB>AlC Composites Prepared by Combustion Synthesis

Abstract

L1 2 -(Al, Cr) 3 Ti/Ti 2 AlC composites have been prepared by the reactive arc-melting technique using elemental powders of Ti, Al, Cr, and C. Resulting composites have been reinforced using 4.5, 9, and 18 vol%Ti 2 AlC in a matrix of L1 2 trialuminide Ti-61 mol%Al-13 mol%Cr alloy. The Ti 2 AlC particles having a rod-like morphology of 1.5 µm width and 5-20 µm in length were homogeneously dispersed in the matrix. The matrix grain size was reduced through addition of Ti 2 AlC particles. These composite materials have revealed higher mechanical properties (bending strength and fracture toughness) than that of the monolithic alloy. This improvement is attributed to the Ti 2 AlC particles dispersion and to the fine grain of the matrix.

Synthesis of TiAl(Cr)/Ti<SUB>2</SUB>AlC Composites by Reactive Arc-Melting

“…19) In the present investigation, densification was achieved by a newly developed reactive arc- melting technique. [20][21][22] Using this process, it becomes possible to form an intermetallic matrix having ceramic dispersoids, and to produce the composite material fully dense without applying external pressure. In this work, TiAl(Cr)/Ti 2 AlC composites were produced using this new technique.…”

Microstructure and Mechanical Properties of Ti-B-N Cast Alloys Prepared by Reactive Arc-Melting

“…[5][6][7][8] By this process, it becomes possible to form the titanium alloy containing higher nitrogen and ceramic dispersoids, and to produce the Ti(N)/TiB composite material with full density. This study also evaluated microstructures and mechanical properties of the Ti-B-N cast alloys, e.g., micro-hardness, strength and ductility by bend testing.…”

Hot-Tensile Properties of <I>In Situ</I> Synthesized Multiple-Reinforced (TiB+TiC+Nd<SUB>2</SUB>O<SUB>3</SUB>)/Ti-Alloy Composites

“…Recently, several in situ technologies have been developed in synthesizing discontinuous-reinforced titanium matrix composites in order to avoid interfacial contamination and get fine interfacial bonding, such as self-propagation high-temperature synthesis (SHS), 11,12) powder metallurgy (PM), 13,14) rapid solidification processing (RSP), 15,16) mechanical alloying (MA) 17,18) and ingot metallurgy technique (IM). [19][20][21][22] But these in situ technologies all need specific equipments. In our research, multiple reinforced titanium matrix composites can be in situ synthesized utilizing the equipments and processing route for producing titanium alloys with only adding some reactants in the raw materials and adjusting some of the processing parameters, which is beneficial to decrease the cost of titanium matrix composites.…”