Abstract: The invention relates to high strength aluminium—based alloy of Al—Zn—Mg—Cu system and the articles made thereof. The present alloy is characterized by the combination of improved properties: flowability, technological plasticity, fracture toughness while preserving high levels of strength properties. Said alloy comprises (mass. %): Zn 6.35-8.0 Si 0.01-0.2 Mg 0.5-2.5 Fe 0.06-0.25 Cu 0.8-1.3 Zr 0.07-0.2 Cr 0.001-0.05 Ti 0.03-0.1 Mn 0.001-0.1 Be 0.0001-0.05 and at least one element from the group of alkali-earth metals: K 0.0001-0.01 Na 0.0001-0.01 Ca 0.0001-0.01 Al-balance the sum Zr+2Ti≦0.3%, and the ratio Si:Be≧2.

Abstract: A manufacturing method for a hollow stabilizer comprises a primary pipe manufacturing process for subjecting a seam-welded pipe to hot reduction working, thereby obtaining a primary pipe, and winding the primary pipe in a coil, a cold drawing process for subjecting the primary pipe to cold drawing so that the rate of reduction in area is not lower than 30%, thereby obtaining a thick-walled pipe having a wall thickness ratio of 0.20 to 0.27 higher than that of the seam-welded pipe and tensile strength of 800 N/mm2 to 1,000 N/mm2 is obtained, an internal shot peening process to be carried out as required, a bending process for bending the thick-walled pipe into a desired stabilizer shape in a cold state, an annealing process for subjecting the pipe to stress relieving annealing at a temperature of 300° C. to 450° C., after the bending process, and a shot peening process for shot-peening the annealed pipe.

Abstract: An improved aluminum alloy fin stock is described having both a high strength and a high thermal conductivity. The fin stock contains 1.2-1.8% Fe, 0.7-0.95% Si, 0.3-0.5% Mn, 0.3-1.2% Zn and the balance Al, and is produced by continuously strip casting the alloy at a cooling rate greater than 10° C./sec. but less than 200° C./sec., hot rolling the strip to a re-roll sheet without homogenization, cold rolling the re-roll sheet to an intermediate gauge, annealing the sheet and cold rolling the sheet to final gauge. This fin stock has a conductivity after brazing of greater than 49.8% IACS.

Abstract: A method for heat-treating a hollow cylindrical workpiece includes quench-hardening including a first step and a second step. In the first step, during continuously conveying the workpiece in a horizontal direction without a space between adjacent workpieces, an entirety of the workpiece is subjected to induction-heating conducted from an outside surface of the workpiece only, and a temperature of the workpiece is made uniform before the workpiece reaches a cooling portion spaced from a heating portion. Then, cooling the workpiece is initiated before the temperature of the workpiece falls to Ar3 temperature and an entire cross-section of a wall of the workpiece is quench-hardened. In the second step, during continuously conveying the workpiece in the horizontal direction, induction-heating is conducted only to an outside portion of the workpiece, the induction-heating being conducted from the outside surface only.