Properties of the thermally stable Al95Cr3.1Fe1.1Ti0.8 alloy prepared by cold-compression at ultra-high pressure and by hot-extrusion

• Published in: Materials characterization 2012-04, Vol.66, p.83-92
• Main Authors: VOJTECH, D, MICHALCOVA, A, PRUSA, F, DAM, K, SEDAA, P
• Format: Article
• Language: English
• Subjects: Aluminum; Applied sciences; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Mechanical properties; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Microstructure; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Physics; Powder metallurgy; Rapid solidification; Solidification; Thermal stability
• ISSN: 1044-5803; 1873-4189
• DOI: 10.1016/j.matchar.2012.02.011

An Al95Cr3.1Fe1.1Ti0.8 (in at.%) alloy was made into rapidly solidified powder by melt atomization. The powder was compacted by two processes: 1) uni-axial cold compression at an ultra-high pressure of 6GPa and 2) hot extrusion at 480°C. The structures, mechanical properties and thermal stability of both materials were compared with the commercial AlSi12Cu1Mg1Ni1 (in wt.%) casting alloy, which is generally considered to be thermally stable. It was found that cold compression at ultra-high pressure created a compact and porosity-free material, which was similar to the material that was prepared with the commonly used hot extrusion method. The Vickers hardness, compressive strength and compressive yield strength of the cold-compressed alloy were 161 HV, 680MPa and 547MPa, respectively, which were higher than the values obtained for the hot-extruded and casting alloys. The thermal stability of the hot-extruded Al95Cr3.1Fe1.1Ti0.8 alloy was excellent because its mechanical properties did not change significantly, even after 100h of annealing at 500°C. The mechanical properties and thermal stability of the investigated materials were discussed in relation to their structures and diffusivities of the alloying elements. ► The Al95Cr3.1Fe1.1Ti0.8 alloy was prepared by compression at an ultra-high pressure of 6GPa. ► The resulting material was dense and porosity-free. ► The material had high hardness of 161 HV and a compressive strength of 680MPa. ► The material had excellent thermal stability at 500°C.