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    Casus Products>> Casus

      51B20 has stable chemical composition, low harmful elements, the purity of steel is high, the advantages of small decarburized layer, good surface quality. After spheroidize annealing, the cold heading property is excellent. The product has good hardenability. Mainly used in the production of 10.9 high strength bolts, suitable for construction, machinery and other fields, widely used in exports.