Numuerical Analysis Of Quenching Process Of Aluminum Alloy T-Shaped Forgings

Aluminum alloys are used for aerospace applications because of their good property combination of high specific strength, high specific stiffness, toughness and stress corrosion resistance. In order to improve its mechanical properties, aluminum alloy forgings require solution heat treatment followed by a rapid quench and a subsequent artificial aging treatment. The quenching part of this process cause high residual stress and distortion such as warping, twisting. Which results in expensive repair costs even scrapped of aluminum alloy forgings. Therefore, the study on the evolution of residual stresses and distortion of aluminum alloy forgings in quenching process is essential.In this paper, the temperature field, the stress field and distortion of the aluminum alloy T-shaped forgings in quenching process were analyzed using experimental, theoretical analysis and numerical simulation methods. The effects of different factors on residual stress and distortion were discussed. The main work focuses on the following aspects:(1) Obtained the cooling curves of the T-shaped specimen with different orientation into water by quenching experiments. Analyzed the heat transfer condition of different regions on T-shaped specimen surfaces, and determined the heat transfer coefficients which are the important basis of numerical simulation for temperature field.(2) Established the numerical analysis model of quenching process of aluminum alloy T-shaped forgings, taking into account the impact of material properties with temperature changing and different regions’ heat transfer. And the temperature field and the stress field of aluminum alloy T-shaped forgings were coupled analysis. The distribution of the temperature field and the stress field in quenching process were studied, the history of the formation of residual stress and distortion was analyzed.(3) The effect of rib size, the clamp holding and the orientation into water on the residual stress and distortion were analyzed. Determined the influence range of rib’s width on residual stress inner web, analyzed of the quenching residual stress and distortion of T-shaped forgings in different clamp holdings, different clamp holding gaps and different quenching orentations.