Any tips on how I can make this in Vray? I guess the same tips would apply for any rendering software. Like what kind of texture map if the final form is a ring? (with a square cross-section) Can the hammered shape be made without actually messing with the geometry? Like would a displacement or bump map be enough?
A displacement map should be fine for this.
I’d not use bump, as you like to have the jagged edges meet.
Circular/tubular texture map on the outer rim, separate circular map on the sides.