if you look back a few pages you will find I posted the same issue after bending all my DBM irons, 2 of them cracked (and they were not the ones that were bent the most)
Can the DBM finish split when bending
I asked my metals genius mate to see what he could do – for fun. he put the CIG welder on the DBM M Series wedge and instantly blew a hole out of the hosel. It was hilarious and scary at the same time. He thinks that might have been from either some glue residue left inside the hosel, or the reaction from whatever the DBM surface is or both. He admitted its hard to know how to treat this without knowing what the black material is.
Anyway, with that experience in hand he went to town on the 7 iron DBM head grinding the black metal off where he needed to weld and despite now being uglier than frankenstein he assured me that it will either instantly break or last forever. I now use this 7 iron head as my driving range club, so probably hit 1000 balls already – and its fine.
I have since replaced both heads with brand new ones from Golfworks, and took the punt and bent them to 3 degree flat successfully, Overall It was a fascinating learning exercise, and I cant tell the difference between my frankenstein 7 iron, and the good one … unless I look at it.