The technology using oxygen-blowing into the bath has been elaborated to decrease gas content in remelted Hadfield steel scrap. This technology was tested and described by means of twenty melts with special respect to blowing conditions and suppressing the formation of gas holes in the castings. It was estimated: Using the remelting technology described in the paper, blowing of oxygen can be used to reduce C content by a mean 0,051 wt.%. When 0,1 wt.% C is removed, 0.024 wt.% N and 2.9 wt.ppm H are removed from the bath under the given conditions. If this technology is used, including addition of 1.5 kg.t~(-1) FeTi 35%, nitrogen gas holes in Hadfield steel castings are safely eliminated and the final content of nitrogen and hydrogen in castings are (250+-72) wt.ppm and (5.5+-1.0) wt.ppm, respectively. Oxygen-blown melts (remelted) have a critical nitrogen content limit around 400 wt.ppm, and a corresponding hydrogen content limit around 8 wt.ppm, for the occurrence of the gas holes in Hadfield steel castings.
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