White iron is the main body of automobile exhaust pipe, and stainless steel is better. If the rear section of the exhaust pipe needs to be modified due to corrosion perforation, it can be welded. It is recommended to go to a professional exhaust pipe repair shop for welding.
If the rusty place is not very big, you can go to the place where there is gas welding and ask the master to trim the rusty place and gas weld it on the better stainless steel skin. But it didn't last long. Better change it.