code1949:
@Neospector
IRON cannot (as far as I know of) be modified to melt at higher temperatures, BUT, SPRK cannot melt, so, if you create SPRK with a ctype of IRON, the IRON will only melt when SPRK's kife reaches zero, so you can set how long it takes to melt and corrode.
OR
You can shield the iron with INSL and DMND, change its life value, when the life reaches zero it will dissipate, so set the life to a value so the the INSL and DMND disappear after the IRON corrodes.