Burning Metal

You cause any objects made of metal in your sight to glow red-hot. Any creature in physical contact with the object takes 6d6 fire damage when you cast the spell. Until the spell ends, you can use a bonus action on each of your subsequent turns to cause this damage again.

If a creature is holding or wearing the object and takes the damage from it, the creature must succeed on a Constitution saving throw or drop the object if it can. If it doesn't drop the object, it has a disadvantage on attack rolls and ability checks until the start of your next turn.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd. when you cast this spell using a spell slot of level 6th the damage dice changes to a d8, and gives 8d8 of damage using 6th level spell slot and 9d8 if used with a 7th level spell slot.  If used with an 8th level spell slot or higher it gives 10d10 fire damage.