電磁鋳造法により製造したアルミニウム合金ビレットの鋳塊品質に及ぼす溶湯流動の影響 Effect of melt flow on the quality of aluminum alloy billets fabricated by electromagnetic casting
The influence of casting rate and pouring method on the formation of columner crystals and floting crystals were invest igated for the purpose of improving the quality of aluminum alloy ingots. Columnar crystals are created in the center of the billet ingot when casting is performed with a slow casting rate without the reduction of the melt-flow rate. But the reduction of melt-flow rate has a possibility of making the structure equiaxial. Moreover, floating crystals crystallized inside the ingots, move from the center of the ingot to the surface, and coarsen. Its amount increases with an increase of casting rate without the reduction of melt-flow rate. Nucleation and growth of floating crystals largely depend on the flow rate of molten metal rather than on the electromagnetic stirring rate. Floating crystals are, therefore not crystallized provided melt flow in the meniscus is restricted by the reduction of melt-flow rate from the spout.
軽金属 47(1), 10-14, 1997-01-30
The Japan Institute of Light Metals