Whilst removing the security stud from my front wheels to fit new tyres the security socket sheered. The mechanic was using a manual torque wrench not an air wrench. I estimate he had to apply apply 400 N m. The spec is 110 Nm and I tested other studs at 150 (the max on my torque wrench) My Volvo dealer is going to chisel off the security studs.

Question: what is the likelihood of damage to the alloys from either over torquing (how much causes damages?) and by the shock of chiselling off the security studs. Could this cause hair line cracks in the alloys that will only become obvious later?