(武汉科技大学 钢铁冶金与资源利用教育部重点实验室,武汉 430081)
摘 要: 在蠕变应力为5.13~11.06 MPa范围内,研究AZ31镁合金中Zn含量对其高温蠕变性能和蠕变应力指数的影响。结果表明:在同样的蠕变条件下,随着Zn含量的增加,合金的蠕变速率增加,稳态蠕变速率区域缩短;应力指数不仅与Zn含量有关,而且与蠕变温度和应力有关;390 ℃时,不同Zn含量的AZ31合金几乎具有相同的应力指数;420 ℃时,Zn含量为0.78%的AZ31合金随应力增加出现n=1和n≈3的两阶段变化,Zn含量为1.53%的AZ31合金随应力增加则出现应力指数分别为n=1、n≈3和n=6的三阶段变化。
关键字: AZ31镁合金;高温蠕变;应力指数
of AZ31 magnesium alloy
(Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,
Wuhan University of Science and Technology, Wuhan 430081, China)
Abstract:The effect of zinc content on the high temperature creep property and creep stress exponent of AZ31 magnesium alloy was investigated at the stress ranging from 5.13 MPa to 11.06 MPa. The results show that the creep rate increases and the static creep stage shortens with increasing zinc content in AZ31 magnesium alloy at the same given creep conditions. The stress exponent is decided not only by zinc content but also by creep temperature and stress. The stress exponent of the alloy with different zinc contents has about the same value at 390 ℃. When the temperature rises to 420 ℃, however, the stress exponent of AZ31 alloy with 0.78% Zn changes from n=1 to n≈3. With increasing stress AZ31 alloy with 1.53% Zn has three different values of stress exponent, that is n=1, n≈3 and n=6.
Key words: AZ31 magnesium alloy; high temperature creep; stress exponent