轧制轧制变形对Al-Zn-Mg-Cu合金中S相破碎情况的影响

针对传统的对称轧制方式难以破碎Al-Zn-Mg-Cu合金中粗大S(Al;CuMg)相的问题,根据蛇形轧制变形区的受力特点,通过主应力法分析了变形区内受力最小区域的应力,并建立了7055铝合金在蛇形轧制过程中粗大S相变形的微观有限元模型。采用建立的有限元模型对对称轧制、异步轧制和蛇形轧制过程中7055铝合金中S相的应变进行了模拟,开展了轧制实验和对S相形貌进行观察,对有限元模型的准确性进行了验证。结果表明:微观有限元模型准确可靠;随着非对称因素的增加,板材心部S相的破碎程度增加,即蛇形轧制>异步轧制>对称轧制;蛇形轧制板材表层S相较心部的应变更大、破碎程度更严重。

Influence of rolling deformation on fragmentation of S phase in Al-Zn-Mg-Cu alloy

In view of the problems of difficulty for crushing the coarse S phase(Al;CuMg) in Al-Zn-Mg-Cu alloy by the traditional symmetric rolling method, according to the force characteristics of the snake rolling deformation zone, the stress in the region with the least force in the deformation zone was analyzed by the principal stress method, and the micro finite element model of coarse S phase deformation of 7055 aluminum alloy during the snake rolling process was established. Then, the strains of S phase in the 7055 aluminum alloy during the symmetric rolling, asynchronous rolling and snake rolling processes were simulated by the established finite element model, and the rolling experiment and S phase morphology observation were carried out to verify the diagnostic accuracy of the finite element model. The results show that the micro finite element model is accurate and reliable. With the increasing of asymmetric factors, the fragmentation degrees of S phase in the core of sheet increases, namely, snake rolling>asynchronous rolling>symmetric rolling. In addition, the S phase on the surface layer of sheet during the snake rolling has greater strain and are more severely broken than that of the core.