Development of Al-Li Alloy Castings Excellent in Formability.

摘要

The suitability of coated material for a casting mold used for producing Al-Li alloy excellent in formability was investigated. Visual inspections of the casting surfaces of Al-Li alloys indicated that there were large gas bubble defects due to melt-mold interaction when those were cast into conventional molds consist of SiO_2 sand and phenol resin binder. XRD analysis showed that the main product of the interaction was Li_2O and Li_2CO_3. Except metal mold castings, the quality of Al-Li castings was order of CaO, Al_2O_3, TiO_2, BN, MgO and no-coated sand mold. This order mostly agreed with the standard generation free energy of oxide, except in MgO coated mold.