The Device Design For The Inter-diffusion Coefficient Measurement In Liquid Metals

The diffusion coefficient is one of the most important physical parameters in liquidmetals, and also an essential parameter for the description of the mass transportation. Itcan help us for the understanding of the atom structure and the nature in liquid metals,material design and industrial application. However, available experimental data of thediffusion coefficients are actually not sufficient due to the difficulties of the diffusionmeasurement. In this work, a new kind of diffusion measurement technique: the slidingcell technique is presented. By employing this technique, the influence of the heatingprocess on the isothermal liquid diffusion procedure is avoided, so that the measurementaccuracy is significantly enhanced compared to the conventional long capillarytechnique. In this work, the Al85Cu15-Al75Cu25diffusion couple was selected to check thesensitivity of the Sliding Cell technique, and the result shows a good accordance withthe previous work measured by the X-Ray Radiography technique. And the liquiddiffusion coefficients of the diffusion couple Al70Cu30-Al90Cu10at1023K weremeasured too. It is found that the measured diffusion coefficients show a clearcomposition dependent tendency. Such a tendency is useful for the understanding of themechanism of atomic diffusion and the correlation between diffusion and atomicstructure. We improved the Sliding Cell technique into the Multi-layer Sliding Celltechnique by combining with the merits of Shear Cell technique. And it wassuccessfully implied to measure the diffusion coefficient of Al-Sn alloys.