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  The QSWRCH22A-B produced by Xingtai steel has good surface quality, low decarburization depth and stable composition. It is suitable for producing all kinds of medium and high strength tapping screws and fasteners. The product has been certified by a mainframe factory in China,and the customer reflects the hardenability, Non-metallic inclusions, mechanical properties and other performance indicators of the material can meet the requirements of the product.