Your answer lies somewhere in the intermolecular forces. Chemical bonding and Van Der Waals forces are directly influenced by temperature. The molecular structure of alloys is usually slightly higher than pure metals but Van Der Waals forces are significantly much higher... Add temperature and you have your answer...
In Steel, viscosity measurements show a correlation between viscosity and percentage of carbon (0 Wt%= 5 cP and 4,5 Wt%= 8,5 cP) This correlation can be further explained in terms of increased viscosity as the interatomic distance become smaller. It is to be expected that clusters of Fe3C existing in molten iron-carbon alloys are in dynamic equilibrium and that they diffuse within the melt, decreasing the fluidity.
What would you think would flow down a slide faster: solid balls or solid cubic blocks of similar weight? You're comparing the flow of all the similar size and shape atoms or molecules of a molton pure metal vs. a flow of different size and shape atoms or molecules of an alloy composed of a mixture of different metals..
viscosity of liquid metals
Re: viscosity of liquid metals
