Nova spray

Nova spray is a cocktail from Ironhide's chemical toolkit that turn electrum-objects extremely brittle— not just stripping away the electrum's protective properties, but actually turning the object "as brittle as rusted scrap."

Nova spray is highly combustible, and cannot be used while there is danger of a stray shot. The high-temperature chemical reaction appears to be part of its normal function. If the nova spray is unable to completely penetrate a thick electrum-coated object its surface will turn brittle and crack, but the object underneath will remain unaffected.

''Only Ironhide is able to to apply the nova spray, it's likely that it is something he invented as the Autobots' weaponmaster.