异步叠轧中剪切力对超细孪晶铜制备的影响

Effect of Shearing Stress on Preparation of Ultra-fine Twin Copper During Asymmetrical Accumulative Roll-bonding

采用异步叠轧法辅以热处理制备超细孪晶铜材,研究了异步叠轧对晶粒细化的影响,以及再结晶退火时织构转变的情况。结果表明:异步叠轧过程剪切应力的作用形成了搓轧区,它的形成使变形材料经过该区域发生压缩变形和剪切变形,以及累积叠轧的作用,使晶粒细化到约1μm;由于剪切织构积聚了较强的弹性应力,使得再结晶过程中原子定向生长,总的效果相当于剪切织构{001}<110>旋转54.7°变成了退火织构{111}<211>,也就是孪晶组织。

The ultrafine copper with twins was prepared by asymmetrical accumulative roll-bonding （AARB） and heat treatment. The characteristic of grain refinement and the texture transformation during recrystallization were investigated. The results show that the crossover areas formed by the shear stress during AARB are compression deformation and shearing deformation zone when the deformation of copper occurs in these areas. The average grains size reduces to 1 μm by AARB. The strong elastic stress accumulated by shearing texture is responsible for oriental growing of a great number of grains during recrystallization. The shearing texture {001}〈110〉 rotates 54.7° and transforms ,into annealing texture { 111 } 〈211〉, which is twin microstructure.