A304? If you are referring to ASTM A304, that's not stainless steel. There are generally two grades of 304 stainless steel....304 and 304L, with the "L" designating lower carbon content. These are also generally known as 18-8 stainless steels, referring to their Chromium and Nickel contents respectively.
Both have good corrosion resistance but can be pitted by caustic materials (mortar is caustic initially, but moderates rather quickly to a reasonable pH.
304, 308, or 316 stainless steels are acceptable for your application. In structural angle, you might not have a lot of choice of availability.
316 stainless is (was) usually readily available and will work.
I used 316 for embedded steel in rocket test stands and it held up well considering the nasty chemical environment and the cryogenic problems. Being a rookie at the time, the idea of 316 structural shapes for valve and walkway support (including hardware) seemed to to be a little excessive along with the 316 grating, but time proved it was the right decision, especially with the conditions and malfunctions. - No problems with the concrete reactions.
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
Will it be possible for someone to share the general structural notes for SS? I have some angles and a few square tubes on this project and can't find any notes in our library.
WWTEng....there should be no thermal difference between stainless and carbon steel. Neither is particularly good. Not sure where the architect is coming from on that one.
As for welding the angle to metal studs, you are mixing two very difficult welding procedures, so I would go with mechanical fastening.
Not all stainless steels are easily weldable...most structural shapes are, but you will almost always get corrosion at the weld because of the different metallurgy of the filler metal and the base metal. Then you have to look at the weldability of metal studs. Those are sheet metal and require specific welder qualification different than structural welding with thicker materials....the welder would have to be qualified for both. Next you have the difficulty of determining the integrity of the welds. There are few nondestructive methods that would provide any relevant information, so you're left with purely a visual inspection...in my opinion not sufficient for such a mixture of procedures and materials.
