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  The Q10B21 produced by XINGTAI STEEL has stable composition, low harmful elements, small decarburization layer, few surface defects, and excellent hardenability. it can directly reduce production costs because of its non annealing processing. A customer of XINGTAI STEEL used this steel grade to produce 8.8 grade bolts. The customer reported that the product has stable drawing performance, no cracking during cold heading, and stable performance after heat treatment.