Abstract: The invention relates to the production of protective coatings with a dark color by pickling rolled flat objects, made from titanium zinc, for use in construction. The flat objects are pickled in an aqueous pickling bath containing a mixed acid of sulphuric acid and nitric acid and passivated after rinsing by application of a protective layer. Rolled flat objects such as those made from a titanium zinc alloy are used. The alloy comprises mainly zinc of high purity with additionally a copper content of 1.0 to 2.0 wt. %, a titanium content of 0.06 to 0.2 wt. % and a maximum aluminum contant of 0.015 wt. %.

Abstract: The invention relates to the production of protective coatings with a dark color by pickling rolled flat objects, made from titanium zinc, for use in construction. The flat objects are pickled in an aqueous pickling bath containing a mixed acid of sulphuric acid and nitric acid and passivated after rinsing by application of a protective layer. Rolled flat objects such as those made from a titanium zinc alloy are used. The alloy comprises mainly zinc of high purity with additionally a copper content of 1.0 to 2.0 wt. %, a titanium content of 0.06 to 0.2 wt. % and a maximum aluminum contant of 0.015 wt. %.

Abstract: Deep-drawable sheets and strip are produced on a continuous casting machine with moving flexible belts and continuous finish-rolling without change of direction from a zinc-copper-titanium rolling alloy which is creep-resistant according to DIN 17 770 and foldable according to DIN 1 623. The alloy contains 1.5 to 5.5% copper, 0.05 to 0.25% titanium and, if desired, 0.005 to 0.05% aluminum, balance zinc. The zinc-copper-titanium alloy, wherein an increase in copper content is accompanied by a decrease in titanium content, is continuously cast into a slab having a thickness of 6-24 mm and a width from about 0 to 2000 mm, preferably 500-1500 mm. The slab is caused to solidify simultaneously and uniformly from both sides at a constant volumetric solidification rate and the slab is subjected to hot-rolling at temperatures above 100.degree. C and at least 3, preferably 5 passes, each of which results in a reduction in cross-section not in excess of 80%.