When you think of water, do you picture it sizzling through metals. I didn’t. One of my most valuable reference finds, a retrospective by a key nuclear engineer, enlightened me:
Strange as it may seem, pure water under high temperature and pressure is a most corrosive liquid, as corrosive as some acids. We set up an extensive program to develop the alloys needed for the components – primary loop piping and pressure vessel cladding – that would be in contact with the coolant water. These were tested under simulated reactor conditions. We installed a few autoclaves at Bettis . . .
What the heck is an autoclave, I wondered? Wiki tells us: “An autoclave is a pressure chamber used to carry out industrial processes requiring elevated temperature and pressure different from ambient air pressure.”
Simpson, John W. 1995. Nuclear Power from Underseas to Outer Space. American Nuclear Society, La Grange Park, Illinois, p. 331.