Dynamic recrystallisation and dynamic precipitation in AA6061 aluminium alloy during hot deformation. (September 2014)

• Record Type: Journal Article
• Authors: Fan, X. H.; Li, M.; Li, D. Y.; Shao, Y. C.; Zhang, S. R.; Peng, Y. H.
• Is Part Of: Materials science and technology. Volume 30:Number 11(2014:Nov.)
• Page Start: 1263
• Page End: 1272
• Publication Date: 2014-09
• Subjects: Aluminium, -- Flow stress, -- Dynamic recovery, -- Geometric dynamic recrystallisation, -- Dynamic precipitation; Materials science -- Periodicals; Microstructure -- Periodicals; Metallurgy -- Periodicals; 620.1105
• DOI: 10.1179/1743284714Y.0000000538
• Languages: English
• ISSNs: 0267-0836

Abstract

Abstract : Deformation behaviour of AA6061 alloy was investigated using uniaxial compression tests at temperatures from 400 to 500°C and strain rates from 0·01 to 1 s −1 . Stress increases to a peak value, then decreases monotonically until reaching a steady state. The dependence of stress on temperature and strain rate was fitted to a sinh-Arrhenius equation and characterised by the Zener–Hollomon parameter with apparent activation energy of 208·3 kJ mol −1 . Grain orientation spread analysis by electron backscattered diffraction indicated dynamic recovery and geometrical dynamic recrystallisation during hot compression. Deformation at a faster strain rate at a given temperature led to finer subgrains, resulting in higher strength. Dynamic precipitation took place concurrently and was strongly dependent on temperature. Precipitation of Q phase was found in the sample deformed at 400°C but none at 500°C. A larger volume fraction of precipitates was observed when samples were compressed at 400°C than at 500°C.