A cumulant expansion for the size distribution of liquid droplets during phase separation (original) (raw)
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International Journal of Materials Research, 2009
im Weltraum,D eutschesZentrumf ür Luft-und Raumfahrt (DLR),K öln,G ermany Microstructuree volution during aliquid-liquid decompositionundert he common action of the nucleation,growthand Ostwald ripening of droplets The kineticdetailsof the microstructureevolution during a liquid-liquid phasetransformationundert he commonaction of the nucleation,diffusionalg rowthand Ostwald ripening of the minority phasedroplets areinvestigated numerically.The results demonstratethatthe cooling rateduring the nucleationperiod of the minority phasedroplets has anoverwhelminglystrong effecton the microstructureformation compared withthe cooling rateafterthe nucleation period.Generally,the effectof the Ostwald ripening of the minority phasedroplets isweakinanalloycooledcontinuouslyall through the miscibility gapand the average radius of the minority phaseparticlesshows aninversesquareroot dependenceo ncooling rate. Ano bvious coarseningo fthe minority phased roplets occursand the exponentialvaries towards-1/3 onlywhen the cooling ratedecreasesbymore thantwoorders of magnitude afterthe nucleation of the precipitated droplets.