半连续铸造和热处理工艺对锌铝合金管材性能的影响

Influence of Semi-continuous Casting and Heat Treatment Process on Properties of Zn-Al Alloy Pipes

研究了在半连续铸造、热处理工艺和挤压工艺条件下,Zn-22Al合金铸棒与挤压管的显微组织和力学性能。结果表明,相较传统井式炉铸造,经过半连续铸造的Zn-22Al合金铸棒品质好、致密光洁、晶粒细小,杂质更少,氧化不明显,挤压前可省去超塑性处理工艺。经过传统铸造挤压成形的管材最多只能减径至φ6.4 mm,而经过半连续铸造挤压成形的管材可拉拔减径至?5.8 mm,不仅减少了工序,而且提高了管材塑性。

The microstructure and mechanical properties of Zn-22Al cast rods and extruded tubes were investigated under semi-continuous casting process,different heat treatment processes and extrusion processes.The results indicate that compared with the traditional pit furnace casting,the Zn-Al alloy casting rods by semi-continuous casting presents dense and smooth microstructure with high quality,fine grains and less impurities as well as less casting oxidation,indicating the omission of superplastic process before extrusion.The outer diameter of the pipe extruded by traditional casting extrusion is reduced to 6.4 mm to the greatest extent,while that extruded by semi-continuous casting can be reduced to 5.8 mm,which not only reduces the process,but also improves the plasticity of the pipe.