Steady quality Canter Fe449 Rear Wheel Bolt

1. Selection of high-strength bolt raw materials

The correct selection of fastener materials in fastener manufacturing is an important part, because the performance of fasteners is closely related to its material. Cold heading steel is a steel for fasteners with high interchangeability produced by cold heading forming process. Because it is formed by metal plastic processing at room temperature, the deformation amount of each part is large, and the deformation speed is also high. Therefore, the performance requirements of cold heading steel raw materials are very strict.
(1) If the carbon content is too high, the cold forming performance will be reduced, and if the carbon content is too low, it will not be able to meet the requirements of the mechanical properties of the parts.
(2) Manganese can improve the permeability of steel, but adding too much will strengthen the matrix structure and affect the cold forming performance.
(3) Silicon can strengthen ferrite to reduce cold forming properties and material elongation.
(4) Although boron element has the effect of significantly improving the permeability of steel, it will also lead to an increase in the brittleness of steel. Excessive boron content is very unfavorable for workpieces such as bolts, screws and studs that require good comprehensive mechanical properties.
(5) Other impurity elements, their existence will cause segregation along the grain boundary, resulting in the embrittlement of the grain boundary, and the damage to the mechanical properties of the steel should be reduced as much as possible.