Abstract:Pinning austenite grain boundaries and inducing acicular ferrites(IAFs) by means of fine oxides are theoretically analyzed. The oxides mainly form in deoxidizing process of liquid steel with big size and small volume fraction, therefore they cannot effectively pin the austenite grain boundaries, also are hard to induce IAF in austenite grains. A large amount of nitrides can precipitate in steel, in line with both requests of effective pinning grain boundaries and inducing IAFs.
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