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  The GML20MnTiB-B is mainly used to produce 10.9 grade fasteners. The product has stable composition, small decarburized layer, less surface defects, easy spheroidizing annealing during use,and less tendency of grain growth when carburizing. A customer of XINGTAI STEEL used this product to produce automobile wheel bolts, which shows that the product has stable performance and low cold heading cracking rate.