Effects of Boronizing Treatment on Corrosion Resistance of 65Mn Steel in two Acid Mediums

To explore the soil workability of rotary blade suitable for large tilling depth (over 20 cm) manufactured through boronizing treatment, this work focuses on the corrosion behavior of 65Mn steel after boronizing treatment in two acid mediums, i.e. the strong acidic medium that hydrochloric solution and the weak acidic that fertilizer-containing soil, and the comparison with existing technology of general rotary blade (lonnealing after overall quenching). The result shows that the corrosion resistance in the two acid mediums of 65Mn steel after boronizing treatment is remarkably improved. After 168 hours' corrosion in the hydrochloric acid solution, the weight loss of boronizing-status sample is only 27.9% of that of lonnealing-status sample. Moreover, there is no obvious weight loss in boronizing-status sample after 168 hours' corrosion in the fertilizer-containing soil, while the weight of lonnealing-status sample is lighter than the original weight after about 150 hours' corrosion. The improvement of the corrosion resistance lies in the significant reduction of the anodization speed in strong acid medium and the effective prevention of phosphorization reaction in weak acidic medium.