1. 熔化，熔毁(以再利用)
    If an object is melted down, it is heated until it melts, so that the material can be used to make something else.

1. reduce or cause to be reduced from a solid to a liquid state, usually by heating

    e.g. melt butter
           melt down gold
           The wax melted in the sun

    Synonym: meltrun