退火工艺对5A06挤压型材组织及性能的影响

Effect of Annealing Process on Microstructure and Properties of 5A06 Extruded Profiles

采用观察显微组织和测试硬度、电导率、力学性能等方法研究不同退火工艺对5A06挤压型材组织及性能的影响。结果表明:在250~450℃退火温度范围内,晶粒无明显长大趋势,强度、延伸率趋于平稳;当退火温度达到450℃时,电导率及硬度达到峰值;当退火温度超过450℃时,粗晶数量明显增多,晶粒随温度增加严重粗化,强度、硬度、电导率大幅降低,延伸率明显提高;采用炉冷时的电导率和硬度值整体上高于空冷。

The effects of different annealing process on the microstructure and properties of 5 A06 extruded profiles were investigated by means of observing microstructure and testing hardness,conductivity and mechanical property.The results show that the grain size shows no obvious growth trend within the annealing temperature range of 250℃to 450℃,and the strength and elongation tend to level off.The conductivity and hardness reach the peak value as the annealing temperature reaches 450℃.The amount of coarse grains increases obviously as the annealing temperature exceeds 450℃,the grains become severely coarse with increasing temperature,and the strength,hardness and conductivity reduce greatly,the elongation improves obviously.The conductivity and hardness values as furnace cooling are overall higher than that as air cooling.