In-Depth Comparison of An Industrially Extruded Powder and Ingot Al Alloys

• Main Authors: David Bombač, Peter Cvahte, Martin Balog, Goran Kugler, Milan Terčelj
• Format: Article
• Language: English
• Published: MDPI AG 2020-11-01
• Series: Metals
• Subjects: aluminum powder; hot extrusion; hot compression; activation energy
• Online Access: https://www.mdpi.com/2075-4701/10/11/1483

An industrial press was used to consolidate compacted aluminum powder with a nominal diameter in the range of 1 µm. Direct and indirect hot-extrusion processes were used, and suitable process parameters were determined from heating conditions, ram speeds and billet temperatures. For comparison, a direct-extrusion press for hot extrusion of a conventional aluminum alloy AA 1050 was used. The extruded Al powder showed better mechanical properties and showed a thermal stability of the mechanical properties after annealing treatments. To increase the theoretical density of the directly extruded Al powder, single-hit hot-compression tests were carried out. Activation energies for hot forming were calculated from hot-compression tests carried out in the temperature range 300–580 °C, at different strain rates. Processing maps were used to demonstrate safe hot-working conditions, to obtain an optimal microstructure after hot forming of extruded Al powder.