AL 29-4C® alloy, is a superferritic stainless steel developed by ATI Allegheny Ludlum in the early 1980s specifically for power plant surface condenser tubing. Since that time over 60 million feet of superferritic condenser tube has been put into service. The alloy has excellent resistance to brackish, polluted or high chloride waters, e.g., seawater. AL 29-4C alloy has also outstanding potential for use in tubing for desalination equipment and has seen extensive use in high efficiency furnace equipment. While maintaining all attributes of conventional ferritic stainless steels, AL 29-4C alloy provides the following advantages over other competitive materials:
1. High resistance to severe chloride environments, such as seawater
2. Better resistance to vibration damage than titanium
3. Better resistance to erosion-corrosion than titanium and copper base alloys
4. Better heat transfer properties than austenitic stainless steels
5. Low cobalt content
6. Cost effectiveness.

Tubes produced from properly manufactured AL 29-4C material should be capable of passing the ASTM G48 Practice C pitting test when tested at 70°C for 72 hours with the sample in the as-produced condition.