FORMATION OF HIGH TEMPERATURE CORROSION PRODUCTS OF AISI 310S AUSTENITIC STAINLESS STEEL.

The Formation of high temperature corrosion products in chloride containing environment was investigated by optical microscopy. Chloride environment originated from chemically preparation of hydrochloric solution, then boiled it until meets boiling point, and finally fed through nozzle into horizontal chamber, which was heated up from ambient to 900°C, in term of acidic vapor. The test results obtained that chromium carbide and sigma phase precipitates at grain boundaries and within austenite matrix. The formation of chromium carbide and sigma phase are mutually complex reaction. The precipitation effects to generate chromium depleted zone and would lead to intergranular corrosion. The high temperaturechloride containing environment results in oxide and chloride corrosion products on stainless steel surface. Moreover, wet condition deteriorates to chromium oxide film and produces ferrous oxide combined with chloride metalliccompounds.