Materials

USP One Base, Three Carbon Windows — Alloy 800, 800H and 800HT share a single iron-nickel-chromium composition range, and the

USP Two Acid Families, One Chemistry — Molybdenum and copper carry reducing-acid duty while chromium handles oxidising media, and as

USP Carbon Sets the Service Ceiling — Carbon at 0.15% caps Nickel 200 near 315 °C; in contrast, the 0.02%

USP Aging Sets the Strength — First, aluminium and titanium precipitate during the heat treatment, and yield ends up near

USP Alloy 400 Grade File — Chemistry, corrosion envelope, and mechanical minimums for UNS N04400 sit on one page, so

USP Above 20% Chromium — The grade holds the highest chromium level of the C-family, so nitric acid and wet

USP Mixed-Acid Chemistry — Molybdenum and tungsten carry reducing acids while chromium handles oxidizing streams, so one grade covers both