Extrusion of Al-Si alloy compacts under conventional conditions and in the semi-solid state

5th International Conference Recent Trends in Structural Materials

Zygula, K.^1 ; Lypchanskyi, O.^1 ; Wojtaszek, M.^1 ; leboda, T.^1

AGH University of Science and Technology, Faculty of Metals Engineering and Industrial Computer Science, Av. Mickiewicza 30, Cracow, PL

30-059, Poland^1

关键词: Deformation process;    Hot extrusion process;    Isothermal conditions;    Processed materials;    Punch displacement;    Temperature stability;    Uni-axial compression tests;    Uni-axial pressing;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/461/1/012096/pdf
DOI  :  10.1088/1757-899X/461/1/012096

来源: IOP

【 摘 要 】

In this research work the results of hot extrusion process of aluminium alloy compacts conducted at the temperature of conventional hot extrusion as well as at the temperature range corresponding to the semi-solid state were presented. Initial material was prepared by uniaxial pressing of Al17Si5Fe3Cu1.1Mg0.6Zr alloy powder. The extrusion process was carried out under isothermal conditions, and the temperature stability was strictly controlled. The changes of extrusion force in relation to punch displacement were recorded during hot deformation to demonstrate the effects associated with the appearance of the liquid phase in the volume of the processed material. After extrusion the samples were cooled in water as well as at room temperature. The influence of temperature of extrusion and the resulting fraction of the liquid phase in the processed material on its microstructure and chosen mechanical properties were determined. Mechanical properties of the examined alloy after deformation were carried out by measuring the hardness and in uniaxial compression tests. Additionally, one of the compacts was remelted and cast, what made possible comparison of the microstructure and chosen properties of the obtained products. In the result of the investigations it has been proved, that extrusion in semi-sold state results in reduction of forces necessary to complete deformation process and leads to obtaining the material with good mechanical properties and fine-grained, favourable microstructure.