添加剂对镁合金微弧氧化的影响

为了解添加剂对镁合金微弧氧化陶瓷膜的成膜速度及微观组织结构的影响,用自制的微弧氧化实验装置对AZ91D压铸镁合金进行了微弧氧化,并用SEM、XRD分析其微观组织结构.结果表明,在槽液中添加Al复合化合物使起弧电压和稳态电压降低,氧化陶瓷膜的生成速度增加、硬度增大,膜层致密性提高,陶瓷膜中的晶胞以垂直于基底面的方式生长,陶瓷氧化膜中主要存在的相有Al2O3、MgAl2O4和MgO.但当含Al复合化合物的质量分数在30%以上时,其致密性和硬度反而下降.

Effect of Additive on Micro-plasma Oxide Film of Magnesium Alloy

In order to understand the effect of additive on the film forming speed and the microstructure of the micro-plasma oxide ceramic film of magnesium alloy,AZ91D die cast magnesium alloy are oxidized with a special micro-plasma apparatus,and the microstructure of ceramic film is investigated by SEM and XRD.The results show that the addition of additive containing Al to electronic solution enhances the film forming rate of oxide film,increases its density and hardness(HV) greatly and decreases the primary and steady plasma voltage.The crystal cellular in the ceramic film grows perpendicularly to base of AZ91D alloy during micro-plasma oxidation,and the microstructure of the film consists of Al_2O_3, MgAl_2O_4 and MgO phases.However,the density and hardness(HV) of the ceramic film decrease as the percentage of the compound additives is more than 30%.