When cast, this spell made metal act as a liquid. As it did not melt the metal via temperature change, the liquid metal remained the same initial temperature it was before the spell was cast. It remained a liquid until the spell expired, at this point it returned to its solid state in whatever shape the liquid was in. For example, if cast onto a sword, the sword turned liquid and formed into a puddle and when the spell expired, the puddle became solid metal. If cast on a magical object, it lost its magical abilities and was made useless.