For your goal, molten metal is not suitable, or at least, has no benefits.  

Metals are generally good conductors of heat. So all that heat from the Sun will be distributed quickly throughout the metal blob, until all sides are at equilibrium temperature. That will be a bit lower than the temperature from direct insolation (the sphere will radiate heat in all directions, so some of the heat will be redirected away from the satellite). 

You'd achieve the same with a solid metal shield with a large radiator. This would be much easier to control than a liquid blob.