20th International Forgemasters Meeting - IFM 2017

Nitrogen is needed for high Cr steel to improve corrosion-resistant and heat-resistant. In generally, nitrogen adjust method in ESR is addition of nitride briquette. However, in this method, nitride does not melt and might remain in an ESR ingot as inclusions. On the other hand, the addition of powder nitride isn’t suitable because yield for this method is too low. In this study, we investigated a new nitrogen addition method during the ESR melting. As a new nitrogen addition method, the nitride powder cored wire was welded to an electrode and was melted together. Fe-N-Mn and Fe-N-Cr were used as a nitride powder. As a result, it was confirmed that nitrogen increased the both ESR ingots. The electrode welded the Fe-N-Cr powder cored wire was higher in nitrogen yield. It seemed that this cause is difference in slag dipping depth by a melting point of nitride. A tendency about the nitrogen increment was higher from center to surface in middle part of the ingot. It seemed that this cause is difference of metal pool temperature. However, the difference in nitrogen increment of the diameter direction is not fatal. These results suggest that nitrogen addition method using nitride powder cored wire is effective.