Manufacturing method of aluminum alloy for railway vehicle body

Abstract

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.

Description

technical field [0001] The invention relates to the technical field of aluminum alloy material processing, in particular to a high-temperature preparation method of aluminum alloy for rail vehicle body. Background technique [0002] With the maturity of my country's high-speed rail vehicle manufacturing technology and the deepening of international promotion, the requirements for aluminum profiles of high-speed rail vehicles are getting higher and higher. At present, most domestic high-speed rail trains use 6000 series, 7000-series aluminum alloy structural profiles, but the 6000-series body aluminum profiles are prone to unstable fatigue resistance, and the 7000-series body aluminum profiles are prone to poor corrosion resistance. The reason for the above problems is mainly that in the aluminum alloy melting and casting stage, the melting temperature of 6N01 aluminum alloy is higher than 760 ° C, and the melting temperature of 7N01 aluminum alloy is higher than 750 ° C. High...

AI Technical Summary

Problems solved by technology

[0002] With the maturity of my country's high-speed rail vehicle manufacturing technology and the deepening of international promotion, the requirements for aluminum profiles of high-speed rail vehicles are getting higher and higher. At present, most domestic high-speed rail trains use 6000 series, 7000-series aluminum alloy structural profiles, but 6000-series body aluminum profiles are prone to unstable fatigue resistance, while 7000-series vehicle body aluminum profiles are prone to poor corrosion resistance

The reason for the above problems is mainly that in the aluminum alloy melting and casting stage, the melting temperature of 6N01 aluminum alloy is higher than 760 ° C, and the melting temperature of 7N01 aluminum alloy is higher than 750 ° C. High temperature melting will cause serious burning problems and cause segregation of the ingot. Coarse grains and feathery grains are prone to appear on the surface and inside of the ingot, which deteriorates the internal structure of the ingot

[0003] In addition, the existing 7000-series aluminum alloys belong to hard alloys, and the yield of extruded products is generally low, resulting in a lot of waste. In order to realize the recycling of waste, it is necessary to increase the proportion of waste in raw materials. However, a small amount Adding scrap can have a positive effect on the performance of aluminum alloy ingots, but adding a large amount of scrap will seriously affect the performance of the ingot

Images