INVESTIGATION OF THE MARANGONI MOTION ON TERNARY AL-SI-BI ALLOYS UNDER MICROGRAVITY CONDITIONS

Two samples of the ternary system Al-Si-Bi were heated up to the liqui d miscibility gap under microgravity conditions to investigate the Mar angoni motion in a defined temperature gradient. On the basis of X-ray absorption images and micrographs determined by light microscopy the general feature of droplet movement and droplet coagulation are discus sed. Differences between the calculated and experimental values of the mean droplet radius show that beside Marangoni motion other particle growing processes took place.