Mechanical and Corrosion Properties of Fe–B–C Alloys

Abstract

Mechanical and corrosion properties of Fe–B–C alloys (0.1–9 wt% B; 0.2–4 wt% C; Fe is balance) were investigated. Microhardness and compressive strength, resistance to abrasive, and gas-abrasive wear of the alloys were determined at room temperature. The corrosion rate was measured by gravimetric method in the following aqueous solutions: 0.5 M H₂SO₄ , 5 M H₃PO₄ , 0.8 M HNO₃ , 1 M HCl , 2 M CH₃COOH , 3 M NaCl, and 0.2 M Na₂SO₄ . The highest resistance to abrasive wear is shown by Fe–B–C alloys with high hardness and the highest resistance to gas-abrasive wear – by the alloys with high compressive strength. In a majority of the acidic and neutral media, the corrosion rate of Fe–B–C alloys decreased with increasing time due to the accumulation of corrosion products on the surface of the samples. The corrosion rate increased with an increase in the volume fractions of eutectic and austenite phases in the eutectic colonies or when interfaces between the primary and peritectic phases were formed in the structure. The Fe–B–C alloys demonstrated the highest corrosion resistance in the sodium chloride solution and the lowest one in the nitric acidic solution.