Alcan International Limited

Novelis, Inc.

Geoffrey M Scamans

John A Hunter

Nigel J Holroyd

Wilfred B O'Callaghan

David Skingley Wright

Paul A Wycliffe

Christopher John Davenport

Warren Hepples

Daniel B Miller

There is provided a method of texturing a metal sheet or strip (), which method comprises a plurality of sequential texturing passes each of which is performed by passing the sheet or strip () between at least one pair of rollers (), wherein at least one of each pair of rollers () has a textured pattern on the surface thereof and the textured patterns are transferred to the sheet or strip () during each texturing pass, and wherein the textured surface on the sheet or strip () resulting from each pass overlaps with that from the one or more other passes to form a final textured pattern. There is also provided an apparatus for texturing a metal sheet or strip ().

Method and apparatus for texturing a metal sheet or strip

An aluminum battery comprises an aqueous alkaline electrolyte and an anode which is an alloy of aluminum containing magnesium and/or calcium. Tin is present in the electrolyte (as stannate at a concentration of 0.001 to 0.01 M) and/or in the anode (at a concentration of at least 0.005%). The batteries operate at high coulombic efficiency at both high and low current densities. Preferred conditions of operation comprise drawing current at an average current density of 5 to 400 mA/cm.sup.2 of anode surface for at least one hour, and introducing seed crystals into the electrolyte to aid precipitation of aluminum values from the electrolyte.

Aluminium batteries

Welded structures composed of aluminium alloy components are protected from white zone and exfoliation corrosion by means of a surface layer applied over the weld bead and consisting of an aluminium alloy containing 0.02 to 0.4% by weight of indium. Other elements which may be present include zinc 0.1 to 1.5%; manganese, 0.02 to 0.5%; tin, 0.12 to 0.50%; gallium, 0 to 0.2%; and magnesium, 0.01 to 6%. The surface coating may be applied by arc or flame spraying or by welding.

Welding aluminium alloys

A high amp-hour aluminium battery comprises a cathode, an alkaline electrolyte and at least one massive aluminium anode plate. The electrolyte contains dissolved indium. The anode is an alloy of aluminium with manganese and with one or both of magnesium and calcium and optionally gallium. When operated at a current density below 400 mA/cm.sup.2 particularly in the presence of seed crystals, the battery remains viable during and after aluminium hydroxide precipitation in the electrolyte.

Problems are caused by stress corrosion cracking and exfoliation cracking in the heat-affected zones adjacent welds in structure of welded components formed of Al alloys, particularly of the 7000 series but also of the 5000 series. The invention seeks to overcome these by the use of Al-Mg welding wire containing 0.01-0.5% Ga and/or In and/or Sn, the composition being chosen such that the weld bead has a potential at least as electronegative as the components and preferably in the range -1200 to -1300 mV with reference to a standard calomel electrode. To prevent diffusion of Ga/In/Sn, the components may be pre-coated e.g. by using a double-pass welding technique.

Growing community of inventors

Cropredy, United Kingdom

Geoffrey M Scamans