اثر ترکیب روی بافت کریستالوگرافی در آلیاژهای AL-Li-Cu

Effect of composition on crystallographic texture in hot-rolled Al-Li-Cu alloys

اثر ترکیب روی بافت کریستالوگرافی در آلیاژهای AL-Li-Cu نورد گرم شده

ABSTRACT

The hot-rolling textures of ternary Al-Li-Cu alloys have been characterized to determine their effects on the yield strength anisotropy. The alloys used in the study had (Li/Cu) ratios varying from 0 to co and were hot-rolled in the 520-400 “C temperature range. All the alloys showed well developed p-fibers, with a maximum intensity at Brass, and a weak background of a-fiber. The Brass components were very strong for the alloys with intermediate (Li/Cu) ratios that had relatively more T, precipitates in the microstructure compared with other alloys. In addition, all compositions showed a weak Cube or rotated Cube recrystallization texture components. The observed textures are attributed to the effects of constrained deformation during hot deformation. The texture results were used to predict the yield strength anisotropies in the alloys. The predictions were in agreemenwt ith the experimentalr esultsf or the high (Li/Cu) alloys. However, in the low (Li/Cu) alloys, the discrepancies between the predicted and the measured yield strength anisotropies can be attributed to a modifying effect of the directional platelet precipitates on deformation.