Steve Siebeck

High-strength aluminum-based light-weight materials for safety components – recent progress by microstructural refinement and particle reinforcement

Abstract High-strength materials on the basis of aluminum are attractive candidates for use in applications such as safety components that require high strength, high quality and integrity of various properties. In this paper, we discuss recent improvements in terms of property optimization made in the fields of (1) ultrafine-grained aluminum alloys prepared by equal-channel angular pressing, and (2) aluminum matrix composites with particle reinforcement. We discuss microstructural aspects and mechanical properties, as well as technological (processing parameters), wear and corrosion behavior. Our results highlight recent — and potential for further — improvements and for future applications of high-strength, aluminum-based materials.

Powder Metallurgy of Particle-Reinforced Aluminium Matrix Composites (AMC) by Means of High-Energy Ball Milling

This paper deals with the production of aluminium matrix composites through high-energy milling, hot isostatic pressing and extrusion. Spherical powder of the aluminium alloy AA2017 (grain fraction > 100 μm) was used as matrix material. SiC and Al2O3 powders of submicron and micron grain size (< 2 μm) where chosen as reinforcement particles with contents between 5 and 15 vol.% respectively. The high-energy milling process was realised in a Simoloyer mill (Zoz). The milling time was about 4 hours. Hot isostatic pressing (HIP) was used to convert the compound powder into compact material. The extrusion process realises semi-finished products with different geometrical shapes.

Influence of Milling Atmosphere on the High-Energy Ball-Milling Process of Producing Particle-Reinforced Aluminum Matrix Composites

High-energy ball milling (HEM) with subsequent consolidation is a suitable method to create particle-reinforced aluminum materials. In addition to other parameters, the used PCA (process control agent) as well as the atmosphere significantly influence the milling procedure. The present article deals with the influence of different milling atmospheres (air, argon, nitrogen) on the high-energy ball-milling process when milling an Al alloy with SiC particles. The investigations show that the reaction of the ground material with air, when rinsed with air, changes the milling behavior of the aluminum powder significantly. Unlike with inert atmospheres, the use of a process control agent (PCA) is therefore no longer necessary.