For a project I am working on, I need a container that is both highly corrosion resistant and strong (able to withstand pressure). I was thinking about stainless steel. Basically, the container needs to be able to hold up to a concentrated solution of Sodium Hydroxide (NaOH), if you look at this web page, http://www.coleparmer.com/techinfo/chemcomp.asp Leave, “Materials” set to “All”, and Select the “Chemical” to be Sodium Hydroxide (80%)”, you can see how various substances will hold up to that concentrated of a solution of NaOH. Now I will not be using a 33.3 Molar Solution of NaOH in real life (mostly because I would like to maintain the use of my eyes for a few more years at least), but why not test the material to the extreme in theory at least (also you will notice that 316 Stainless steel’s rating doesn’t change between 80% and 20% solutions). The second requirement, strength, pretty much rules out plastic as a possible container material, since some of the best plastic to hold up to NaOH do not cope with pressure very well. Ideally, I should also be able to get the material easily and cheaply. So it looks like Stainless Steel is my best bet. However, there are so many types/grades of stainless steel; I don’t know which is right for me. 316 stainless steel supposedly hold up against NaOH well (so says the list on that web page), but I wouldn’t know where to get it, and it is probably expensive. Then I had a great idea, a pressure cooker! It is already made into a container, it of course can hold pressure, it is made from stainless steel, and it is pretty easy to get one (just go on down to the store). But the type of stainless steel concerns me, all the pressure cookers I can find say they are 18/10 stainless steel, I have no idea what this means (it is probably a ratio of certain components to the steel). How does this compare to 316? Wikipedia has a page on stainless steel, http://en.wikipedia.org/wiki/Stainless_steel and it includes a section on the different types, it says that type 316 is used “for food and surgical stainless steel uses”. But I don’t see anything about 18/10 So does anyone have any advice on my stainless steel dilemma?