Recent Developments for the Production of Al-Mg Compounds

Abstract

The changes of ecological awareness of political initiatives give new rules for economy and industry with the aim to support environmental friendly technology. Research projects are focusing on lightweight designs especially in automotive and aerospace industry. This paper deals with the results of the application of lightweight materials, in detail with aluminum-magnesium-compounds and its manufacturing process. Thereby, the process chain from the production of semi-finished parts and the first subsequent process will be explained in detail with focusing on the modification of the intermetallic interface. The combination of hydrostatic co-extrusion and subsequent performed forging is an auspicious approach for the production of lightweight parts made of Al-Mg-compounds. In this contribution the main influencing parameters, experimental and numerical work, interface properties as well as the process analysis will be explained in detail.

Forging of eccentric co-extruded Al-Mg compounds and analysis of the interface strength

“…By using aluminum and magnesium as compound materials, both goals could be reached. The production by hydrostatic coextrusion -with AZ31 as core material and AA-6082 as sleeve material -results in a complete bonding [1]. The bonding could be maintained during further processing by forging [2].…”

“…As sleeve material the aluminum alloy AlMgSi1 (AA-6082) and as core material MgAl3Zn (AZ31) were used. A detailed description of the co-extrusion process of Al-Mg compounds can be found at KITTNER [1]. The bonding quality of the rods has been examined by ultrasonic testing.…”

A Fragmentation Criterion for the Interface of a Hydrostatic Extruded Al-Mg-Compound

“…The compound together with the interface was under examination regarding production process and resulting bonding quality, strength of the basic materials, interfacial strength, residual stresses, fracture mechanical properties and formability [5][6][7][8][9] as described below. The formability of such hybrid structures including their interface are rarely investigated.…”

“…The outer diameter of the manufactured compound amounts to 20 mm and the inner diameter to 14.5 mm. Further information about the process and optimisation possibilities can be found in [5,7,13,14]. After the manufacturing process at 300 • C, the compound cools down to room temperature causing residual stresses due to differences in the thermal expansion coefficient.…”

“…Investigations regarding the forging processes upsetting, spreading and rising showed a good formability of the compound at 300 • C [5,7,9]. During the heat-up process in preparation of forging, the boundary layer grows up to a thickness of at least 25 µm due to diffusion based processes [22].…”