Heat-treatment of 2014 aluminium alloy forgings with intense strain

摘要

The triangular 2014 aluminium alloy forgings with intense strain were made by a variety of heat-treatment processed, and their mechanical properties were measured. The results showed that different solution and aging processes have very strong influence on the mechanical properties of the forgings. The forgings with intense strain from multidirec- tional deformation (deformation coefficient λ = 12), which were solutioned at deg. C for 400 min and aged at 165deg.C for 10 h, show advanced mechanical properties, and almost no anisotropies. The mechanical properties are σb = 466 MPa, σ_0.2 =454 MPa, δ= 10.5/100 along LD; σb = 457 MPa, σ_0.2 = 444 MPa, a = 6.3/100 along TD; σb = 449 MPa σ_0.2 = 433 MPa, δ = 4.2/100 aling HD. The yield strength of the forgings made by a new process was improved by 30/100 to 50/100, the ultimate tensile strength by 15/100 to 30/100 and elongation by l00/100 to 200/100, compared with the mechanical properties of the forgings made by the traditional process. The investigation indicated that the very fine grains (3 ～6 μm) and the sub- microphases (0.05 ～0.15 μm), and their homogeneous distribution have made the forgings have the high mechanical properties.