| C | Si | Mn | S | P | Cr | Ni | Cu |
| 0.80～0.90 | 0.10～0.35 | 0.10～0.50 | ≤0.03 | ≤0.03 | ≤0.30 | ≤0.25 | ≤0.25 |
Generally, spring steel can be produced using electric furnaces, open hearth furnaces, or oxygen converters; High quality spring steel with good quality or special properties is refined using an electric slag furnace or vacuum furnace. The specified content range of main elements such as carbon, manganese, and silicon in spring steel is relatively narrow, and the chemical composition must be strictly controlled during smelting. When the silicon content is high, defects such as bubbles are easily formed, and white spots are easily produced when the steel ingot is not cooled properly after forging and rolling. Therefore, the raw materials used for smelting must be dried to remove gases and inclusions as much as possible, and to avoid overheating of the molten steel. Special attention should be paid to decarburization and surface quality during the rolling process of spring steel. When the surface of steel is severely decarburized, it will significantly reduce the fatigue limit of the steel. For high silicon spring steel such as 70Si3MnA, attention should be paid to avoiding graphitization. Therefore, the stopping temperature during hot processing should not be too low (≥ 850 ℃) to avoid prolonged residence time in the temperature range where graphitization is more likely to occur (650-800 ℃). After the production of the horse core spring, shot blasting treatment can generate residual compressive stress on the surface of the spring to offset some of the working stress on the surface and suppress the formation of surface cracks, which can significantly improve the fatigue limit of the spring.
1. Used for mold parts that require high hardness and wear resistance due to sliding abrasion, such as guide pins, bushings, ejector pins, etc.
2. Cutting tools, cold heading dies, scrapers, and files for processing wood.
| C | Si | Mn | S | P | Cr | Ni | Cu |
| 0.80～0.90 | 0.10～0.35 | 0.10～0.50 | ≤0.03 | ≤0.03 | ≤0.30 | ≤0.25 | ≤0.25 |
Generally, spring steel can be produced using electric furnaces, open hearth furnaces, or oxygen converters; High quality spring steel with good quality or special properties is refined using an electric slag furnace or vacuum furnace. The specified content range of main elements such as carbon, manganese, and silicon in spring steel is relatively narrow, and the chemical composition must be strictly controlled during smelting. When the silicon content is high, defects such as bubbles are easily formed, and white spots are easily produced when the steel ingot is not cooled properly after forging and rolling. Therefore, the raw materials used for smelting must be dried to remove gases and inclusions as much as possible, and to avoid overheating of the molten steel. Special attention should be paid to decarburization and surface quality during the rolling process of spring steel. When the surface of steel is severely decarburized, it will significantly reduce the fatigue limit of the steel. For high silicon spring steel such as 70Si3MnA, attention should be paid to avoiding graphitization. Therefore, the stopping temperature during hot processing should not be too low (≥ 850 ℃) to avoid prolonged residence time in the temperature range where graphitization is more likely to occur (650-800 ℃). After the production of the horse core spring, shot blasting treatment can generate residual compressive stress on the surface of the spring to offset some of the working stress on the surface and suppress the formation of surface cracks, which can significantly improve the fatigue limit of the spring.
1. Used for mold parts that require high hardness and wear resistance due to sliding abrasion, such as guide pins, bushings, ejector pins, etc.
2. Cutting tools, cold heading dies, scrapers, and files for processing wood.
