DEVELOPMENT OF ANNEALING TEXTURES IN AL-MG ALLOYS

In order to clarify the effects of the annealing temperature and the M E content on the development of the {100}[001] orientation in the anne aling textures nf Al-Mg alloys, high purity Al and Al-Mg alloys contai ning Mg up to 5% were cold rolled 95 % and annealed at temperatures be tween 300 and 450 degrees C. Textures developed in these alloys at eac h annealing temperature were investigated in detail by using the orien tation distribution function analysis. It was found that, in high puri ty Al, the {100}[001] orientation increased remarkably by annealing at higher temperatures. Such increases were mainly caused by the prefere ntial growth of the {100}[001] grain during grain growth. In the annea ling textures of Al-Mg alloys, the {100}(001) orientation was generall y weak. Its development was more strongly suppressed with increasing M g content and with increasing annealing temperature. In these alloys, shear banding which occurs extensively during cold rolling, appears to destroy possible nucleation sites of the {100}[001] recrystallized gr ains. The {100}[001] recrystallized grains observed after complete rec rystallization were thus smaller in number and more widely distributed . During subsequent grain growth, they were therefore readily consumed by grains of other orientations. From these results, it was concluded that the positive introduction of shear bands during colding rolling, combined with annealing at high temperatures, effectively reduces the {100}[001] orientation in the annealing texture in Al alloys, improvi ng their press formabilities.