Combustion synthesis of metal-matrix composites. Part 2: The Ti-Ti{sub x}Al{sub y}-Al{sub 2}O{sub 3} system

Journal Article · Sun Jan 14 23:00:00 EST 1996 · Scripta Materialia

DOI:https://doi.org/10.1016/1359-6462(95)00448-3· OSTI ID:186788

Kunrath, A O; Strohaecker, T R ^[1]; Moore, J J ^[2]

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1. UFRGS, Porto Alegre, Rio Grande do Sul (Brazil). Dept. de Metalurgia
2. Colorado School of Mines, Golden, CO (United States). Dept. of Metallurgical and Materials Engineering

The production of high performance materials (ceramics, intermetallics and composites) by combustion synthesis is receiving considerable attention since the process offers certain advantages with respect to simplicity and a relatively low energy requirement. The methods by which combustion synthesis (or SHS) can be used to produce metal matrix composites were outlined in an earlier paper. The use of excess liquid metal in the combustion synthesis reaction has already been successfully employed to achieve low porosity products. This metallic phase may be generated by an in-situ reduction of a metal oxide or by adding an excess of some metal to the reactants. Coupling a simultaneous consolidation (pressing) process with the SHS reaction has been found to produce dense bodies. This work discussed in this paper is concerned with the synthesis of a metallic/intermetallic matrix composite reaction system which can be represented by equation. With this reaction, high volume fractions of metallic/intermetallic phases can be produced. The metal-matrix produced by this reaction is predominantly a mixture of Ti{sub 3}Al + Ti as indicated in the appropriate area of the Ti-Al phase diagram. Increasing x increases the volume fraction of Ti. TiAl was observed in only one of the four different stoichiometries studied, i.e., x = 1, as detected by XRD. Using this reaction, there is a constant amount of excess Al and a variable excess of Ti. These stoichiometries produce composites with varying Ti-Al ratios that allow the matrix composition of the composite to be varied along the concentration axis of the Ti-Al phase diagram.

• OSTI ID: 186788
• Journal Information: Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 2 Vol. 34; ISSN 1359-6462; ISSN XZ503X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
ALUMINIUM
ALUMINIUM ALLOYS
ALUMINIUM OXIDES
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
COMBUSTION WAVES
COMPACTING
COMPOSITE MATERIALS
INTERMETALLIC COMPOUNDS
LIQUID METALS
PHASE DIAGRAMS
POROSITY
STOICHIOMETRY
SYNTHESIS
TITANIUM
TITANIUM ALLOYS
TITANIUM OXIDES
X-RAY DIFFRACTION