The invention provides an aluminum
alloy sodium-free refining agent and belongs to the technical field of
casting of aluminum alloys. The
sodium-free refining agent comprises the following raw materials in parts by weight: 30-35 parts of K2CO3, 10-12 parts of
potassium fluoroaluminate, 5-10 parts of CaF2, 12-18 parts of LiCl, 3-5 parts of
calcium oxide, 30-35 parts of BalF3, 5-10 parts of K2SiF6, 10-15 parts of C6Cl6, 5-10 parts of TiO2 and 3-8 parts of CaCl. The aluminum
alloy sodium-free refining agent is free of
impurity sodium; meanwhile, rare-earth metals are added into the sodium-free refining agent; the rare-earth metals have high
chemical affinity with
impurity elements such as H2 and S and the like; the rare-earth metals and various
impurity elements form compounds; the influence of harmful impurities can be eliminated; the rare-earth metals have the functions of modifying and refining the aluminum
alloy structure; the
dendrite spacing of the aluminum alloy is effectively reduced; the as-cast grains are refined; the mechanical performance of the alloy is improved; meanwhile, the
smelting temperature of the aluminum alloy is maintained at 710-730 DEG C in the process of using the aluminum alloy sodium-free refining agent, so that the effect of removing impurity elements such as H2 and S and the like is more significant.