Combustion synthesis of elemental powder compacts has been used to produce alloys with compositions corresponding to Al3Ti, Al73Ti24Cr3, and Al67Ti25Cr8. The binary composition exhibits a strong exothermic reaction at ∼665 °C, resulting in formation of single phase Al3Ti with the tetragonal DO22 structure. The heat of formation of the compound at 298 K, δHf(298), was estimated from peak reaction temperature measurements to be −35.0 kJ mol−1. Additions of Cr lowered the reaction initiation temperature and resulted in the formation of intermediate products attributed to Al–Cr reactions. The DO22 structure remained the primary reaction product in Cr-containing alloys. The Cr particles did not completely dissolve during initial reaction; an additional heat treatment at 1200 °C or above was required to homogenize the material, resulting in partial or complete transformation of the DO22 structure to the cubic L12 structure, depending upon Cr content. Homogenization at 1250 °C for 4 h produced material consisting approximately of a 50-50% mixture of the DO22 and L12 structures for Al73Ti24Cr3, and 100% L12 for Al67Ti25Cr8. In all cases, reaction at ambient pressure was accompanied by swelling, resulting in final densities less than 60% of theoretical. Application of external pressure, either during or subsequent to combustion synthesis, produced near theoretical density materials exhibiting a homogeneous and equiaxed microstructure.