High Temperature Oxidation Behavior of Borided Steel

Abstract

This paper deals with the study of the high temperature oxidation behavior of borided steel and boride at various temperatures and time in air. The low carbon steel was used as the material and the immersion bonding was done with boric acid and potassium borate as sources of boron supply. In the case of heating at high temperature in air, the borided steel was expected to be resistant up to about 700°C while Fe₂B fully existed. The apparent activation energy 25.1 kcal/mol was obtained for oxide formation of the boride Fe₂ B in the temperature range from 700°C to 900°C in air. Surface boride Fe₂ B changed as follows with the high temperature oxidation:
Fe₂B→Fe₂B
α-Fe→Fe₂B
α-Fe
Fe-Oxide
Fe-B-Oxide→Fe-Oxide
Fe-B-Oxide