Its Galvanized steel. Normal steel sheets per "Hot Dip Galvanization" treatment ki jati hai to keep it from rusting. Chrome plating may nickel ki layer ke uper chromium ki layer hoti hai...... whereas in galvanization there is a zinc plating to protect the steel. Thing is zinc can rust to..... is per white rust ata hai and to protect it from rusting there is a oily layer over the zinc layer. Paint do not stick to it and even if it somehow does...it will peel off bcoz of the oily layer.
If you sand down the oily layer you will expose the zinc layer..... The paint will stick to it but the paint will wear-off ...... Zinc reacts with the paint binder creating a film which will make the paint to peel off if stratched will finger nail.
Bottom line is....to paint it....... or even plate it will copper or brass........ you need to get rid of the zinc layer first. I read somewhere it can done by applying a weak solution of ammonia over the zinc layer..... not sure.
Waisay aaj kal 3M 1080 wraps buhat "in" hogaye hain..... far easier option I think than getting a galvanized sheet painted.