Hardware items are one of the products for mass consumption. Rolled metal for cold forging shall have the required ductility, uniform mechanical characteristics along the mill length, corresponding chemical composition and shall be free from internal or superficial defects. Standard mechanical characteristics have been reviewed in this document and fracture criteria of calibrated rolled steel 40X have been calculated after its isothermal treatment at different temperatures in nitre bath and subsequent drawing with different deformation degrees. Comparison of synergy fracture criteria showed that rolled stock, treated as per the proposed conditions: bath patenting at the temperature of 400°C and drawing with reduction rate of 5% and 10%, are more preferable, comparing to processing conditions, existing in the industry.
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