Abstract: A composite metal sheet or plate is manufactured by completely immersing an assembly of parallel or substantially parallel metal core sheets in molten metal at a lower melting point than the metal of the core sheets, and after the molten metal has solidified reducing the thickness of the ingot by hot rolling in a direction generally normal to the planes of the core sheets. The method has a particularly useful but by no means exclusive application in the production of reinforced aluminium alloy sheets and plates.

Abstract: An improved water dispersible aluminum powder composition containing from 0.1% to less than 5% of a polyvinylpyrrolidone resin, and processes for its preparation are disclosed. This composition has the advantages that, in comparison to known compositions containing higher levels of polyvinylpyrrolidone, it can be more completely separated from hydrocarbons, and, when used as a water based slurry blasting agent sensitizer is effective in smaller diameter bore holes.

Abstract: Molten metal, such as aluminum, is held within rigid refractory lining means beneath, above and alongside the metal while heaters keep the outside of the lining means at a predetermined temperature desired for the metal, the heaters being surrounded by thermal insulation and the whole being surrounded by a fluid-cooled support. An unusually effective embodiment is pipe, with a tubular refractory liner to carry flowing metal, surrounded by sheathed heating elements controlled to keep the exterior of the tube at least at about the predetermined temperature, with the thermal insulation wrapped around the heaters and the enclosing support being a water-jacketed steel pipe. The operation is essentially adiabatic with respect to the refractory liner, delivering the molten metal essentially at its original temperature, with unusual saving of heat energy. When the heated pipeline has been drained, only easily removed, paper-thin skulls of solid metal remain.

Abstract: A lifting mechanism for a vehicle tail-board or other platform comprises at least one set of two main levers 12, 13 each of which essentially provides three non-colinear pivots defining a triangle, and the two triangles are substantially identical. Corresponding pairs of pivots 12a and 13a, and 12b and 13b, are respectively interconnected by a tilting lever 14 and a link 16, and corresponding pivots 12c and 13c are interconnected by being connected to spaced fixed locations on the tail-board 10. A hydraulic jack 23 is connected between a pin 26 on lever 12 and a fixed bracket 18, which also carries pivot 12a, and operates to move the tail-board in a horizontal attitude between the ground and the vehicle floor level, and a second jack 22 is connected between bracket 18 and a crank arm 21 of lever 14 and operates, when the platform is at vehicle floor level, to move lever 13 bodily in an arcuate path about pivots 12a, and 12b and 12c to swing the tail-board into a vertical attitude.

Abstract: A method and apparatus for reducing "arc blow" in multi-electrode welding of a metallic workpiece. Arc blow is produced by interaction between the magnetic fields produced by the closely spaced arcs and electrodes, and takes the form of the end arcs being attracted inwardly towards the others. This reduces the welding efficiency and the maximum welding speed. The invention reduces or eliminates the arc blow by providing shunts made of magnetically permeable material close to the arc-producing ends of the electrodes at the two ends of the row of electrodes. This reduces the concentration of magnetic flux in these regions and reduces the deviation of the end arcs. The invention can be applied wherever multi-electrode welding is used, but is especially useful when the workpiece is made of aluminum as arc blow is a particular problem with this metal.

Abstract: The specification relates to retro-reflectors of the type used for road signs and markers and vehicle license plates to make these objects more noticeable to road users after dark. In the invention, the surface of a metal substrate is made retro-reflective by applying a layer of an organic polymeric material and adhering glass beads thereto, and then passing the substrate through a roller mill or the like with the glass beads covered by a platen so that the beads form indentations in the metal surface. The presence of the platen allows the pressing (indentation) step to take place without damage to the glass beads or to the layer between the beads and the metal surface. By this means, a hard metal article can be made directly retro-reflective.

Abstract: Fine-grained, formable Al-Mn alloy sheet is produced from strip-cast slab (e.g. twin-roll-cast slab) by including 1.3-2.3% Mn in the alloy, slab annealing the workpiece by heating it to precipitate most of the Mn in fine intermetallic particles, cold rolling the workpiece to sheet of final gauge with an interanneal performed (between successive cold rolling stages) under nonrecrystallizing conditions to reduce the amount of Mn present in solid solution in the aluminum matrix, and annealing the final sheet.

Abstract: An aluminum sheet product is formed from an alloy containing Fe 0.6-1.0%, Si 0.5-0.9% and Cu 0.3-0.5% and includes Ti and B in conventional grain refining amount. Mn is permissible in amounts up to 0.2-0.3% but is preferably held below 0.1%. The Mg impurity content is preferably held at a very low value so as to avoid difficulties with adhesion of lacquer.The principle use of the sheet product is for the production of bottle closures and for that purpose it is preferably produced in a thickness of 0.15-0.25 mm. and in a quality having a low percentage earing and fine grain size. For this purpose the sheet is subjected to a temper cold rolling reduction of 30-60% after the last interannealing treatment. No homogenization treatment is required before hot reduction of the cast ingot and no precipitation heat-treatment is applied to the hot-rolled product before cold rolling.

Abstract: Aluminum alloy sheet at an intermediate temper and directly formable by drawing and ironing into a one-piece can body, containing 0.45-0.8% Mn and 1.5-2.2% Mg, with the following properties: ultimate tensile strength, at least about 38 k.p.s.i.; yield strength, at least about 35 k.p.s.i.; elongation, at least about 1%; earing, not more than about 4%.

Abstract: The invention provides aluminium articles having porous anodic oxide films colored by means of an optical interference effect. In FIG. 4, the article 10 carries a first anodic oxide film 12 with pores 14 enlarged at their inner ends 20 and containing deposits 22. The products may be made by growing a second anodic oxide film 26 underneath the deposits 22 which are preferably of acid-resistant material. X is at least 26 nm, Y is preferably at least 60 nm, Z is preferably 15 nm to 200 nm, (Y+Z) is preferably 75 nm to 600 nm, and W is preferably at least 15 nm.

Abstract: An alkaline-acid end point detector for titration reactions in which the phenomenon of chemiluminescence is used to detect the end point by monitoring, by means of an electronic light detector, the light output of the reaction materials in a light-tight vessel. The output from the detector is differentiated to detect the maximum output which corresponds to the reaction end point. The detector is useful in the determination of acid numbers in oils and greases.

Abstract: A data acquisition system for a hot metal handling operation uses optical transmission of data from a plurality of hot-metal stations to a control computer. Preferably the computer transmits control instructions to operators via the optical link. In an aluminium pot-line arrangement the mobile transceiver may be mounted on the service crane.

Abstract: A process for sparging molten metal comprises passing gas bubbles upwardly through a series of spaced nozzles arranged in a trough or furnace, the nozzles being arranged to prevent lateral spread of emergent bubbles so as to hold down the bubble size to a controlled size and thus increase the surface area/volume relationship to a desired value.The apparatus employed preferably is embodied in a refractory plate having a series of spaced protrusions or ribs on the upper face. Spaced gas orifices are formed in the protrusions or ribs. The lateral spread of the bubbles is checked or hindered when the gas/metal interface of growing bubbles reaches the sides of the protrusions or ribs.

Abstract: Hydrothermal sealing of anodic oxide coatings is promoted and enhanced by pretreating the anodic oxide coating to be sealed in a mildly basic aqueous medium at temperatures up to those required for hydrothermal sealing of the coating.

Abstract: For the removal of alkali metal and alkaline earth metal contaminants molten aluminium (including Mg-free aluminium alloys), is passed through an active bed of particles of material containing aluminium fluoride, maintained continuously immersed in molten aluminium. Alkali metal and alkaline earth metal contaminants react and may release insoluble molten reaction products. In order to avoid plugging of the active bed and achieve removal of molten reaction products the molten metal is preferably passed upwardly successively through an inactive filter layer, an active bed layer and a further inactive filter layer.

Abstract: Sodium oxalate is supersaturated solution in Bayer spent liquor stabilized by the presence of humic material is precipitated by the treatment with an adsorbent which adsorbs the humic material to give an insoluble product, thus removing it from solution and destabilizing the solution with respect to precipitation of sodium oxalate. The preferred adsorbent is activated carbon. The activated carbon can be dispersed in the spent liquor as a fine powder or the spent liquor can be passed through a column of particulate carbon. Precipitation of sodium oxalate can be expidited by addition to seed crystals and/or addition of sodium oxalate solution which is supersaturated at a temperature higher than that of the spent liquor.

Abstract: Aluminum powder compositions, and methods for their preparation, comprising fine particle size aluminum powder, a polyvinylpyrrolidone resin in an amount of 5% to 20%, based on the aluminum, and either a hydrocarbon or a polar liquid medium in an amount of 30% to 50%, based on the aluminum, are described. These compositions find use as sensitizers in slurry-type blasting agents. Compared to known compositions, they are both dust free and substantially non-reactive, on storage, toward the aqueous milieu of such a slurry.

Abstract: Sodium oxalate in supersaturated solution in Bayer spent liquor stabilized by the presence of humic material is precipitated by the treatment with cationic sequestrants which interact with the humic material to give an insoluble product, thus removing it from solution and destabilizing the solution with respect to precipitation of sodium oxalate. Preferred cationic sequestrants are quaternary nitrogen compounds including medium or long chain alkyl groups. Precipitation of sodium oxalate can be expidited by addition of seed crystals and/or addition of sodium oxalate solution which is supersaturated at a temperature higher than that of the spent liquor.

Abstract: The specification relates to retro-reflectors of the type used for road signs and markers and vehicle license plates to make these objects more noticeable to road users after dark. In the invention, the surface of a metal substrate is made retro-reflective by applying a layer of an organic polymeric material and adhering glass beads thereto, and then passing the substrate through a roller mill or the like with the glass beads covered by a platen so that the beads form indentations in the metal surface. The presence of the platen allows the pressing (indentation) step to take place without damage to the glass beads or to the layer between the beads and the metal surface. By this means, a hard metal article can be made directly retro-reflective.

Abstract: In a process for the treatment of fume-laden carbon monoxide evolved in carbothermic reduction of alumina the fume-laden gas is contacted with particulate carbon in a fluidized bed maintained at a temperature, preferably in the range 2010.degree.-2050.degree. C. and above that at which sticky aluminium oxycarbide forms. The temperature of the bed is most conveniently controlled by the rate at which fresh carbon feed material is added to the bed. The hot gas emerging from the bed is rapidly chilled to a temperature below the solidification point of aluminium oxycarbide. This is most conveniently achieved by contact with a large excess of cool alumina/carbon mix in a stream which is continuously circulated through a heat exchange stage.