Hot-tearing characteristics of Al-Li alloys

Effects of Li content and grain-refiner addition on the hot-tearing characteristics of Al-Li binary word alloys (0-3mass%) and the commercial Al-Li alloys (2090, 2091, 8090 and 2219+1.5mass%Li) were investigated by using hindered type hot-tearing test (I-beam test). High strength alloys, 2024 and 7075 were also investigated to compare with the commercial Al-Li alloys. In Al-Li binary alloys, the tearing tendency was decreased with increasing Li content, but was not improved by the grain-refiner addition, and the efficiency of grain refinement was less than in the pure aluminum. In the commercial Al-Li alloys, the tearing tendency was same as 2024 and 7075 alloys in the case of no additioning grain-refiner, but was not so improved by the grain-refiner addition, while in 2024 and 7075 alloys remarkably improved, and the efficiency of grain refinement was less than in 2024 and 7075 alloys.