What are the requirements for making materials of inclined coil spring?
1 High strength In order to improve the anti-fatigue damage and anti-relaxation ability of oblique spring, the material of oblique spring should have high yield strength and elastic limit, especially high yield. In general, the elastic limit of a material is proportional to the yield strength, so the design and manufacturers of coil springs always want a material with a high yield strength.
2. Good plasticity and toughness In the manufacturing process of diagonal coil spring, the material needs to undergo different degrees of processing deformation, so the material is required to have a certain degree of plasticity. For example, the carabiners and torsion arms of tension and torsion helical springs have complex shapes. When the radius of curvature is very small, defects such as cracks and fractures will not appear in the materials of helical springs during processing. Winding or stamping to bend. At the same time, the material should have good toughness when the inclined helical spring is subjected to impact or changing load, which will greatly improve the service life of the inclined helical spring.
3. Excellent surface conditions and fatigue properties Tilt coil springs suffer the greatest surface stress during operation, and fatigue damage usually begins at the surface of the wire. For tilted coil springs used in important occasions, such as valve tilted coil springs, valve tilted coil springs and suspension, spiral coil springs need millions of cycles, tens of millions of cycles or even longer cycle life, which puts forward high requirements on fatigue performance of materials. There are many factors affecting the fatigue properties of materials, such as chemical composition, hardness, steel purity, surface quality and metallographic structure. The surface quality of the material is particularly important.
4. Strict size many skew coil springs have high requirements for load accuracy. For example, the load deviation of the valve deflector coil spring shall not exceed 5%-6% of the specified load. For example, a stretch and compression coil spring with a round wire will have a load deviation of about 4% if the wire diameter is 1% off. It can be seen that strict dimensional accuracy is also very important to ensure the quality of the incline spring.
5. Good uniformity The requirement of material uniformity refers to the requirement of the chemical composition, mechanical properties, size deviation and other indicators to be uniform and stable. If the characteristics of the material are inconsistent in all aspects, it will bring great difficulties to the production of skew coil springs, resulting in discrete parameters such as geometric size, hardness and product load, and even serious non-uniformity may even lead to waste of products.