Effects of cold predeformation on dissolution of second-phase Al 2Cu particles during solution treatment of 2219 Al-Cu alloy forgings

摘要

AbstractCold predeformation (CPD, before solution treatment) at different pre-compressing deformations of 0, 5, and 10% was performed on 2219 Al-Cu alloy forgings, and its effect on the dissolution of second-phase Al2Cu particles during solution treatment was investigated. The results indicated that a higher number of coarse Al2Cu particles dissolved in the Al matrix during solution treatment in samples processed with CPD. Upon increasing CPD from 0 to 10%, the area fraction of the coarse particles decreased from 2.57 to 0.57%, while their mean size decreased from 12.5 to 8.7μm. The corresponding driving force for precipitation during the subsequent aging treatment process increased, the main precipitates in the material transitioned from the θ″ phase to the θ′ phase, and the area fraction of the precipitates increased from 6.1 to 18.1%. As a result, a significant increase in ultimate tensile strength (by 61.2MPa), yield strength (by 63.2MPa), and tensile elongation (by 2.2%) was obtained.Graphical AbstractIn this paper, the effect of cold predeformation (CPD, before solution treatment) on the dissolution of the coarse secondary-phase Al2Cu particles during the solution treatment of 2219 Al-Cu alloy forgings was studied. After the heat treatment, a greater number of the coarse Al2Cu particles dissolved into the matrix. The volume fraction of the coarse particles decreased sharply, the density of the precipitates increased noticeably, and the fracture surface featured with deeper dimples, leading to increases in the ultimate tensile strength, yield strength, and tensile elongation of the deformed samples as compared to those of the undeformed sample.Display OmittedHighlights?Cold predeformation (CPD) was performed on 2219 Al-Cu alloy forgings.?CPD promoted the dissolution of coarse Al2Cu particles during solution treatment.?CPD increased the driving force to precipitate θ′ phases during aging treatment.?Increasing CPD improved the tensile properties of the forgings.]]>