Why can’t 316L stainless steel replace Hastelloy alloys in harsh chemical environments?

316L stainless steel only works well in mild oxidizing corrosion environments and quickly suffers severe pitting, crevice corrosion and stress cracking once exposed to hydrochloric acid, wet chlorine or mixed acid. Its passive film breaks down easily under high temperature and halogen ions. Hastelloy contains high molybdenum and tungsten to stabilize surface protective layers, resisting both oxidizing and reducing corrosions simultaneously. It can run steadily for years in media that rapidly destroy stainless steel, cutting long-term equipment replacement costs.