Study on isotropy treatment process of hot extruded LY12 Al alloy

Anisotropy of micro-deformation due to textural structure in hot extruded LY12 Al alloy bar was investigated by means of measuring the notch change of ring specimens and testing micro-yield strength (MYS). The results show that the notch change in transverse (perpendicular to axis of the extruded bar) direction is about 13 times than that in longitudinal (parallel to axis of the extruded bar) direction, MYS in longitudinal direction is about 1.8 times than that in transverse direction. Thermal-cold cycling treatment (TCT) has no effect on changing anisotropy of micro-deformation. Isotropy treatment process was studied by means of quantitative metallographic analysis and X-ray diffraction test. Treated by the optimum process, the uniform and fine equiaxed grains can be acquired. MYS test shows that the values in longitudinal and transverse directions are close to each other indicating that anisotropy of micro-deformation has been eliminated.