Complex saturation of corrosion resistant steels AISI430 and AISI303 with boron and carbon

摘要

Studies have been conducted on the effect of the degree of doping with chromium and nickel on the formation of boride coatings on steels AISI430 and AISI303. The saturation was carried out in a SNOL-type chamber furnace equipped with a PID controller from a powder saturating medium in an unsealed crucible. A mixture of boron carbide powders (70 wt. %), potassium tetraborate KBF4 (7 wt. %) and graphite-up to 100 % was used as a saturating medium. The process temperature was 900 °C, the saturation time was 2.5 hours. Upon completion of the high-temperature exposure, the crucibles were removed from the furnace and cooled in air to the 50-60 °C temperature. Diffusion coatings with a total thickness of 120 um were formed on steel AISI430 and 75-85 [im on steel AISI303. The thickness of the boride layer for both steels was 45-50 urn.