Microstructures and mechanical properties evolution of an Al–Fe–Cu alloy processed by repetitive continuous extrusion forming

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 2014-08, Vol.612, p.131-139
• Main Authors: Kong, Xiangxin, Zhang, Hui, Ji, Xiankun
• Format: Article
• Language: English
• Subjects: Aluminum alloy; Aluminum base alloys; Applied sciences; Cold working, work hardening; annealing, quenching, tempering, recovery, and recrystallization; textures; Continuous extrusion; Continuous severe plastic deformation; Cross-disciplinary physics: materials science; rheology; Elasticity. Plasticity; Exact sciences and technology; Forming; Materials science; Mechanical properties; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Mechanical property; Metals. Metallurgy; Microstructure; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Physics; Precipitates; Precipitation; Production techniques; Repetitive Conform process; Scanning electron microscopy; Treatment of materials and its effects on microstructure and properties
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2014.06.038

Repetitive continuous extrusion forming process (R-Conform process), as a continuous severe plastic deformation method, was performed on a horizontal continuous casting Al–0.74Fe–0.23Cu alloy. The microstructural evolution and mechanical properties were studied by optical microscope, X-ray diffraction, scanning electron microscope, transmission electron microscope, and tensile testing. The results show that tensile ductility of the Al–0.74Fe–0.23Cu alloy is greatly improved but tensile strength is gradually decreased after repetitive Conform processing. The necking is more intense and the size of dimples becomes bigger with increasing Conform passes. The first pass Conform process induces obviously grains refining, dissolution of AlFe, AlFeSi and AlSi primary phases, strain-induced precipitation and transformation of crystal orientation distributions, but further Conform deformation only changes the redistribution of precipitates. The changes of mechanical properties may be attributed to a complex progress of recovery, recrystallization and redistribution of precipitates during repetitive Conform process.