Abstract: A device for measuring the current amplitude in busbars and other current feeders to the electrodes of a cell for the electrorefining of copper, comprises a Hall generator which can be set with a yoke upon the conductor or bar and which is provided with an amplifier or discriminator circuit operating a display preferably in the form of a linear array of light-emitting diodes.

Abstract: A light-weight vehicle wheel is formed, according to the invention, by shaping a profiled pressed or stamped sheet or band composed of a malleable aluminum alloy (AlMgSl or AlZn4.5Mgl) into the rim or felly, the wheel disk being cast from a casting alloy such as GK(GD)--AlSi12 or GK-AlSi7Mg.

Abstract: A method for the removal of impurities from copper cathodes withdrawn from a copper electrorefining bath in which the cathodes are subjected to ultrasonic vibrations in the KHz. range in heated water which is circulated or subjected to jets and under conditions in which cavitation bubbles can develop along the surfaces of the cathode.

Abstract: To provide a substrate of aluminum with a dark surface layer of high absorption/emission ratio for luminous energy, the degreased and pickled substrate is immersed in a hot chromating bath until an oxide coating of not more than 2.5.mu. thickness is formed thereon. This coating is then colored black in a hot, acidic dyeing solution (pH between about 0.5 and 5) of potassium permanganate and a nitrate of cobalt or copper.

Abstract: A process for the electrolytic refining of metals, especially copper, in which the copper is deposited from an electrolyte on the cathode of an electrolytic cell which comprises periodically reversing the current with a forward pulse time of 2 to 9 seconds and a reverse pulse time of 0.1 to 0.45 seconds.

Abstract: A corrosive solution, designed to accelerate the rupture of workpieces of aluminum and its alloys in stress-corrosion-cracking tests, contains sodium chloride, hydrogen peroxide and sodium acetate dissolved in water, with maintenance of an acidic pH.

Abstract: The exhaust of an internal-combustion engine comprises a muffler of malleable aluminum or aluminum alloy with a heat-resistant inner layer extending at least along a wall portion confronting an inlet for the hot exhaust gases. The heat-resistant layer may be a refractory coating, e.g. alumina, beryllia or zirconia particles in a matrix of Teflon or silicone rubber, or a metallic liner separated from the outer wall by an airspace possibly occupied by rock wool or the like.

Abstract: A hyperboloidal cooling tower has a central post from which is suspended an upper horizontal ring centered on the post. A network of cables strung from the upper ring define a generally hyperboloidal surface, with the cables criss-crossing and the intersections clamped together with clips. A plurality of corrugated aluminum plates is secured inside the array of cables at the clips with the corrugations of the plates extending upwardly. The corrugations of each plate are spread to a greater and lesser extent at different regions along the plate together so that these plates may form a uniform three-dimensional shape. Each of the plates is secured at its central region fixedly to at least one clip and otherwise secured to the clips via stringers which can slide on these clips so as to allow thermal expansion of the plates relative to the cable network and relative to one another.