Architectural aluminum alloy material and process for manufacturing the same

Abstract

There is provided an architectural Al alloy material which undergoes minor loss of proof stress even after a baking finish treatment at a high temperature of 260 to 280° C. and which can be subjected to acute-angle bending, as well as, a process for manufacturing the same. This architectural Al alloy material, which is a hot rolled JIS A3003 material, contains a fiber structure and a recrystallized grain structure having an area ratio of 20 % or less after a baking finish treatment at 300° C. or lower, and undergoes a proof stress loss of 10% or less after the baking finish treatment. The Al alloy material is manufactured only by hot rolling which is carried out under control such that the temperature at the end of rolling be in the range of 290 to 340° C.

What is claimed is:  
     
         1 . An architectural Al alloy material, which is a hot rolled material defined by JIS A3003 (3003 defined by B209 of ASTM); the material comprising, in terms of a structure after a baking finish treatment at a temperature of not higher than 300° C., a fiber structure and a recrystallized grain structure having an area ratio of 20% or less; wherein the material undergoes a proof stress loss of 10% or less after the baking finish treatment.  
     
     
         2 . The architectural Al alloy material according to  claim 1 , having a proof stress and an elongation of 95 N/mm 2  or more and 27% or more, respectively, after the baking finish treatment.  
     
     
         3 . The architectural Al alloy material according to  claim 1  or 2, wherein the baking finish treatment is carried out at a temperature of 260 to 280° C.  
     
     
         4 . A process for manufacturing an architectural Al alloy material comprising the steps of: 
 subjecting an ingot of JIS A3003 (3003 defined by B209 of ASTM) to a soaking treatment; and    subjecting the resulting ingot to hot rolling to be carried out in such a way that it has a temperature of 290 to 340° C. at the end of rolling;    wherein the thus treated ingot is as such applied to a practical use.