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非金属夹杂物和溶入的气体对铸造和变形铝合金的性能有很大的影响,为了排除这些夹杂物,在实践中最常用的精炼方法是用氯气或某种惰性气体来处理。在铝熔体中主要的夹杂物有氧化物、氮化物、碳化物或金属间相。在大气条件下与铝接触的所有气体中只有氢气有较大的溶解度。在目前生产条件下被吸收的氢气几乎都是由大气中的水蒸汽被铝还原出来的,因此被吸收的氢气量是由空气的湿度来决定的。氧气和氨气在高温下与铝及其合金形成稳定的化合物,即氧化物Al O_3和氮化物AlN。这两种化合物在液态和固态铝中
Non-metallic inclusions and dissolved gases have a great influence on the properties of cast and deformed aluminum alloys. In order to eliminate these inclusions, the most common refining method in practice is to treat with chlorine or some inert gas. The main inclusions in the aluminum melt are oxides, nitrides, carbides or intermetallic phases. Of all the gases that are in contact with aluminum under atmospheric conditions, only the hydrogen has a greater solubility. Almost all of the hydrogen absorbed under the current production conditions is reduced by the water vapor in the atmosphere, so the amount of hydrogen absorbed is determined by the humidity of the air. Oxygen and ammonia form stable compounds with aluminum and its alloys at high temperatures, namely oxides Al O 3 and nitrides AlN. These two compounds are in liquid and solid aluminum