SK101895A3 - Process for manufacturing a light metal wheel in a single piece from a wrought aluminium material - Google Patents

Abstract

A process is disclosed for manufacturing a light metal wheel in a single piece from a wrought aluminium material, preferably an alloy of the AlMgSi type, by flow turning or rolling a warm blank. The blank is solution heat treated at temperatures around 530 DEG C, then is quenched and artificially aged at approximately 150 DEG to 200 DEG . The solution heat treated blank is controllably quenched at approximately 200 DEG C, is flow turned or rolled at this temperature, while a further temperature rise is avoided, and is then artificially aged.

Description

Method for manufacturing a one-piece light metal wheel from a molding aluminum material

Technical field

BACKGROUND OF THE INVENTION The present invention relates to a process for producing a one-piece light-alloy wheel, in particular a curable aluminum alloy, by rolling from a blank, rolling to a continuous extrusion or continuous extrusion or final product in hot condition, homogenizing annealing at temperatures from approximately S30C , depending on the alloy, followed by rapid cooling and thermal curing at temperatures from 150 ° C to 800 ° C. AlMgSi-type alloys are particularly suitable for the production of a one-piece light metal wheel.

BACKGROUND OF THE INVENTION [0002] The production of one-piece blanks used in which the flange is in

In known wheel types of this kind, the flange blanks of the cross-section are approximately radially split at right angles and a rim bed is rolled for this purpose. Also used as blanks are cup-shaped blanks in which the rim bed is also rolled out of the respective shaped rim portion by means of a support.

Prior to the splitting and final rolling of the flanged blank or the final rolling of the cup-shaped blank, the blank is heated to a temperature ranging from

150 ’C to 250’ C. Finishing is followed by homogenizing annealing at temperatures of approximately 530 ° C depending on the alloy and further thermal curing at temperatures from 150 ° C to 200 ° C.

The homogenization annealing and rapid cooling of the rolled blank creates the risk of collapse, especially of the rim bed. In addition, the heating required for rolling processing additionally increases the energy costs.

SUMMARY OF THE INVENTION

The object of the invention is to prevent the rolled parts from collapsing whilst at the same time reducing the energy costs of the process of the kind mentioned at the outset.

According to the invention, this object is achieved by the above-mentioned method, characterized in that, after homogenization annealing of the workpiece, depending on the type of alloy, controlled cooling is carried out to a temperature of approximately 200 C. At this temperature so that the workpiece is not the finished product is produced by continuous extrusion or rolling and is then thermally cured.

An embodiment of the invention

Controlled rapid cooling of the non-rolled blank from the homogenization annealing process to a temperature of approximately 200 ° C depending on the type of alloy and subsequent final rolling, completely avoiding collapse of the finished workpiece which could be caused by rapid cooling and subsequent machining on the lathe. Due to the controlled rapid cooling of the workpiece, depending on the type of alloy, to a temperature of approximately 100 ° C, or to reheating to this temperature level, in contrast to known methods in which reheating is carried out from ambient temperature, this method achieves great energy savings. At this temperature level, which, depending on the type of alloy, reaches about 500 ° C, the blanks are split and then continuously extruded or rolled to form the product. Rolling of the workpiece after controlled rapid cooling from the homogenizing annealing temperature here results in an improvement in the formation of the material structure and thus also in its utility properties. Thermal curing then follows in a known manner.

Also within the scope of the invention is a solution according to which rapid cooling after homogenization annealing is realized by a higher cooling rate by means of a water spray with a specified amount of water and water temperature. Thus, good mechanical properties of the material can be achieved. It is also possible for a plurality of workpieces stored in suitable racks to be rapidly cooled by a water spray.

This method finds advantageous use in the manufacture of a one-piece light metal wheel, in particular of an AlMgSi-type alloy.

A further advantage can be seen in the fact that the rolling temperature, which, depending on the type of alloy, is approximately S00 CC, and which must be maintained throughout the extrusion or rolling process, can be used in subsequent thermal curing.

Due to the minimal deformation on the pure rolled blank, the allowances for machining the rim bed can be substantially reduced. This also reduces the runout deviations and imbalance.

Claims (3)

1. A method of making a one-piece light metal wheel of a molding aluminum material by continuously extruding or rolling from a blank in a hot condition and homogenizing annealing at temperatures of approximately S30 ° C, depending on the alloy, followed by rapid cooling; ^r thermal curing at temperatures of from 150 ° C to ¹⁸⁰⁰ "C, characterized in that the homogenization annealing of the blank is carried out a controlled rapid cooling to about 200 ° C depending on the alloy, at which temperature so as not to In order to achieve the finished product, continuous extrusion or rolling and then thermal curing are realized. Method according to claim 1, characterized in that by controlling the cooling of the workpiece after the homogenization annealing, its temperature drops below the rolling temperature, whereupon the workpiece is again heated to the rolling temperature. Method according to claim 1, characterized in that the individual blanks are cooled by a higher cooling rate by means of a water spray with a specified amount of water and a water temperature. Method according to one or more of the preceding claims, characterized in that an alloy of the AlMgSi type is used to make the one-piece light metal wheel.