Aluminum alloy laminate of at least two plated sheets or strips finished by cold bright rolling has high reflectivity on one external face and low reflectivity on other external face

摘要

The two sheets or strips making up the external faces are chosen such that, after the same surface treatment, i.e. chemical or electrochemical etching or brightening, one has a bright face with reflectivity at 85 deg measured in the rolling sense (R85SL) greater than 60%, and the other matt face has reflectivity (R85SL) less than 20 deg . The bright face is, for example, made of aluminum of purity greater than 99.5% or an aluminum-magnesium alloy produced from aluminum of such purity. The matt face is made of an aluminum alloy with a composition such that the surface fraction of the intermetallic compounds is greater than 2.5%, and preferably greater than 7.5%.