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русскийAug 13,2024
The cold headed wire rod is a coil of wire used to produce the various fastener products such as bolts, screws, nails and pins. Cold heading is a cold deformation process that combines upsetting with swaging to improve the strength of a steel product. It is a manufacturing process that requires particular material and processing techniques, including smelting and rolling.
During the smelting and rolling process, strict control of the chemical composition of steel is necessary. It optimizes the material structure, increases plasticity and stability of mechanical properties, and reduces the content of harmful elements. It also avoids surface wrinkles, the appearance of ear lines and other defects.
When producing cold heading quality steel, it is essential to develop a stable austenite microstructure during rolling. This is a prerequisite to achieving an optimal combination of ferrite and pearlite in the final product. The annealing process of this steel is also important in controlling the microstructure, preventing cracks and improving the comprehensive mechanical properties.
Spheroidize annealing has been studied to enhance the mechanical properties of spheroidizing annealed wire rod steel. It is found that the dispersed cementite and coarse ferrite grains after spheroidize annealing can contribute to high tensile strength, ductility and ultimate tensile strength. It is believed that the spheroidize annealing method can provide the optimum microstructure for cold heading quality wire rod.
The manufacturing of cold headed fasteners is a highly complex process that requires the use of specialized dies and tools. The tool life is greatly affected by the quality of the raw material and the production technique of the wire. It is important to control the amount of reduction, rolling pass and number of times of turning, obtaining a uniform and fine grain structure with low ear lines and surface wrinkles.
Stock Code: 000906