The invention relates to a manufacturing method of aluminum
alloy for a railway vehicle body. The manufacturing method of the aluminum
alloy sequentially includes the steps of prepurging,
smelting, primary refining, secondary refining, standing,
casting and homogenizing, and further includes the
superheating treatment process and the
quenching process. After primary refining, aluminum
alloy melt is subjected to
superheating treatment and
quenching and then subjected to secondary refining. By performing
superheating treatment on the aluminum alloy melt, the melt structure is switched into a disordered state from a short-range ordered state similar to a
solid phase; then, by performing
quenching rapidly, molten aluminum alloy is rapidly cooled to a
casting temperature without loosing effects. In this way, the number of active
crystal nucleuses generated by non-spontaneous
crystallization of the molten aluminum alloy is reduced; although spontaneous
crystal nucleuses are small, the structure of a cast
ingot can be better refined, and a more compact cast
ingot structure can be obtained. The performance of the aluminum profile produced by the cast
ingot in the method is better than that of aluminum profiles produced by cast ingots in traditional methods.