The properties of high temperature aluminum (HITEMAL, hereinafter HIT) composites made of powders with different particle sizes ranging from 0.8-3 μm and purities of 99.9%-99.996% were tested. The thermal, electrical, and mechanical properties of these materials were examined and compared with pure Al. Three different HIT materials were used for the outer sheath of single-core MgB 2 wires with a Ti barrier manufactured by internal magnesium diffusion into a boron process. The critical currents, thermal stability, and strain tolerances of the MgB 2 /Ti/HIT wires were measured at liquid He temperature. It was found that the Al powder purity and particle size used for HIT affect the performance of MgB 2 wires. A sheath made of high purity Al powder allows better thermal stability of MgB 2 wire, but the strain tolerance is lower in comparison to the wire with HIT made of less pure powder and higher Al 2 O 3 content. The presented wire configurations are promising for lightweight, thermally stabile, and strain tolerant superconducting MgB 2 wires.