The Aging Behavior And Mechanical Properties Of Deformed2A14Aluminium Alloys

The heat treatment process of the aluminum alloy is closely related to themicrostructure and the mechanical properties. The effect of different treatment process,such as hot rolling, cold rolling, and aging, on the microstructure and mechanicalproperties of2A14aluminum alloy is researched by DSC, SEM, TEM, tensile test andhardness test.The experimental results show that there are α-Al matrix, Al2Cu phase and a smallamount of Mn-containing phases in squeezed2A14aluminum alloys and the coarsephases were broken and distributed in a certain direction. The solution heat tempeturelimit was509℃. After solution treatment, Al2Cu dissolved in the alloy. There are somerodlike T phase dispersed in the matrix of the2A14aluminum alloy after solutiontreatment. The coarse phases were broken after rolling and distributed in rolleddirection. There are a lot of fine phases formed after hot rolling.The tensile strength, yield strength and elongation of the2A14aluminum alloywith small deformation all increased first and then decreased with the extension ofaging time. The elongation of the2A14aluminum alloy decreased with the agingtemperature increasing at the same aging time. The2A14aluminum alloy with smalldeformation exhibited ductile fracture with dimples after aging.There are no precipitation or precipitated rarely when the2A14aluminum alloywith small deformation aging at150℃for4h. Ω phase and S’ phase formed in thealloy when aging at150℃for10h,. With the increase of aging temperature andextension of aging time, the content and size of S’ phase increased. When aging at180℃for4h, the S’ phase start to precipate on dislocation. Precipitation on the grainboundary is S phase and there are no precipitate free zones in the vicinity of the grainboundaries.The orthogonal test shows that the influence of cold rolling deformation on thetensile strength, yield strength and hardness of the2A14aluminum alloy is biggest,and hot rolling deformation on elongation is the biggest. The study found that thetensile strength and elongation of the alloy cold rolled directly after solid solution werelower than the alloy cold rolled after hot rolled. The experimental results show that themicrostructure of hot rolled2A14aluminium alloy is improved. Yield strength andelongation of the specimens along the rolling direction were higer than specimens perpendicular to the rolling direction, but the tensile strength is same.