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  Q37MnB5 material is a kind of European standard steel developed by Xingtai Steel. It is base on common carbon structure steel, adding trace boron element and increasing manganese content to improve that hardenability of steel and reducing cold-heating deformation tension. A customer of Xingtai Steel uses the steel to produce automobile engine structure parts and 10.9 grade high strength bolts. The customer reflects that the product has stable chemical composition , good cold heading performance and low inclusion content , and can fully meet the requirements .