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Aluminum-Lithium alloys were developed as major replacements for existing aluminum alloys to reduce the weight of aircraft and aerospace structures. Mechanical properties of Al-Li alloys greatly depend on solidification conditions. Other than reducing the microsegregation, homogenization treatment has other effects on the microstructure of Al-Li ingots. In this research, effects of homogenization treatment at constant temperature (500°C) on the precipitation in the microstructure of Al-1Li-3Cu-0.1Zr (wt %) and Al-2Li-3Cu- 0.1Zr (wt %) specimens have been investigated. Results show that homogenization at 500°C for 24 hours not only increases the hardness and phases precipitating in grain but also reduces microsegregation of Fe in grain boundaries.

Sintered metal powder process is one of the high technology methods in ceramic–metal joining processes. Improvement in joining zone properties is very important in this method. The present study reveals the effect of metalised layer sintering temperature and time, and applied layer thickness on tensile strength and thermal shock resistance of alumina–copper joint. The results reveal that primary sintering for holding time duration of 90 min at a temperature of 1530°C and applied layer thickness of 50 μm with proper different stages of plating and brazing leads to a tensile strength of 120 MPa in the joining zone. The specimens, which were joined in this condition, were thermal shock resistance.