DYNAMIC RECOVERY AND DYNAMIC RECRYSTALLIZATION OF 7005 ALUMINIUM ALLOY DURING HOT COMPRESSION

查看全文 作　　者：J. Shen;S. S. Xie and J. H. tang (General Research Institute for Non - ferrous Metals,Beijing 100088, China) 出　　处：《Acta Metallurgica Sinica(English Letters)》索引2000年第13卷第1期,共8页 摘　　要：Dynamic recovery and dynamic recrystallizatin behaviors of AA7005 aluminium alloy (Al - Zn - Mg) during hot compression are investigated by isothermal compression testing.The interdependence of flow stress,stress, strain rate,true strain and deformation temperature for the alloy is analyzed by introduc- ing Zener-Hollomon parameter. A steady - state flow of the 7005 alloy is confirmed to be a thermal- ly activated process.which is governed by rate-controlling mechanisms of dislocations.A hyperbolic sine relationship can satisfactorily correlate temperature, strain rate with flow stress through an Arrhe- nius term that involves thermal activation parameters. The dynamic recovery mechanisms of the alloy are discussed.Cross- slip of jogged screw dislocations is the main dynamic recovery mechanism over the deformation temperatures and strain rates.Subgrains are highly developed in the originally elongat- ed grains.The size of the subgrain increases with decrease of the natural logarithm of Zener- Hol - lomon parameter.Local dynamic recrystallization is operative when the alloy is deformed at temperature of 500℃ and strain rate of 0. 001s - 1. 关 键 词：compression flow stress DYNAMIC recovery DYNAMIC RECRYSTALLIZATION RESTORATION mechanism