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The common defects of nitric acid-grade 18/10L (00Cr18Ni10) stainless steel can be divided into two main categories: corrosion-related defects and manufacturing-related defects. 1. Corrosion-related defects: Sensitized intergranular corrosion – After remaining in the sensitization range of 450–850°C for an extended period, chromium carbide precipitates at the grain boundaries; corrosion along these grain boundaries can still occur in environments with hot concentrated nitric acid. In the case of small-sized thin-walled tubes, improper heat treatment can result in a corrosion rate of over 1 mm/year. Over-passivation corrosion: In high-temperature concentrated nitric acid at concentrations of over 68%, the material enters an over-passivation region, where the corrosion rate increases significantly, leading to corrosion defects characterized by uniform dissolution. Chloride-induced pitting/stress corrosion: When in contact with chlorinated media, the surface passivation film is locally damaged, leading to the formation of pitting pits; under residual tensile stress, this can also induce stress corrosion cracking. II. Defects related to production and processing: During the raw material stage, these include metal ball marks, longitudinal cracking, foreign object indentation, folds, etc. Cold rolling stage: roll imprint, roll vibration marks, fishbone defects, wavy defects, etc. Annealing and pickling stage: over-pickling, under-pickling, pitting, white spots, residual pickling solution, etc. Finishing stage: poor degreasing, uneven grinding, burrs, etc.