North American Stainless (NAS), 100% subsidiary of Acerinox, S.A., is leader delivering stainless steel rebar in the USA market. 289 metric tons of stainless steel rebar, duplex 2304, manufactured by NAS has been used to build the new Hastings Bridge on the Mississippi river, in Minnesota, USA. This bridge stands out because its 166 metre long curved hollow sections are the longest in the USA to date.
As US Transport Departments are better informed about the benefits of using stainless steel in bridge restoration, the use of stainless steel reinforcement bars is increasing in this country.
For this particular project, duplex 2304, a grade with an austenite and ferrite micro-structure of almost identical proportions gives a very high resistance to atmospheric corrosion. It was chosen from amongst several other alternatives due to its superior compatibility with the climate of the state of Minnesota with its long winters and the subsequent need to regularly use thawing salts. Although the initial outlay was higher, this grade will bring a significant cost saving to the state of Minnesota during the life cycle of the bridge, which is estimated to be 100 years.