硬铝LY_（12）超塑性变形的显微组织研究

Study on the Microstructure of Hard-Aluminum Alloy LY12 in Superplastic Deformation

本文对超塑性形变过程中的组织变化进行了研究．发现超塑性形变过程中，特别是形变前期，如果晶内滑移形变量过大，会引起材料产生局部动态再结晶．在超塑性形变后淬火，在品界附近观察到位错线和位错缠结．在超塑性形变的晶粒长大过程中，只要存在粘性变形，晶界一直保持一定宽度．若形变停止后，宽晶界将变成细小的普通晶界．

In this paper,The Microstructure of hard-Aluminum Alloy LY12 in superplastic deformation is studied. It is discovered that. If slip deformation within grains is over large in suplastic deformation, the local dynamic recrystallisation will occur and result in uneven growth of grains and produce unusual coarse grains, hereby the superplastic elongation will diminish. When quenching hard-aluminum alloy after superplastic deformation, dislocation lines and tangled dislocations are observed on the vicinity of grain boundary.If only producing viscous deformation grain boundaries will all along remain a difinite width. If stopping the viscous deformation in the fluidized-zone crystallization will take place and wide grain boundary will change into narrow grain boundary.