Structure and properties of ultra-fine grained aluminium alloys produced by severe plastic deformation

Methods of imparting ultra-fine grained (UFG) structure to conventional aluminium alloys by thermomechanical treatment, including severe plastic deformation, are analysed. The effect of initial structure parameters, such as grain size and precipitates of secondary phases, on UFG structure formation is discussed in terms of physical mechanisms. Ambient temperature mechanical behavior of UFG alloys produced by several methods is reported. The effect of grain refinement on static strength and toughness is more pronounced in non-heat treatable alloys. Evolution of UFG structure during post-deformation heat treatment and superplastic behavior of UFG alloys is shown.