C75 carbon steel is a high-carbon, non-stainless steel, equivalent to SAE 1075, CK75, known for good strength, wear resistance, and spring properties, making it ideal for knives, springs, saw blades, and hand tools.
C75 carbon steel is equivalent to SAE1075, AISI1075, CK75 steel which is a high-carbon spring steel known for its excellent strength, durability, and elasticity, containing around 0.75% carbon, making it ideal for manufacturing springs, blades (like saw blades, knives), circlips, shims, and automotive parts, available in various thicknesses and widths, often supplied hardened and tempered or annealed for shaping before heat treatment.
C75 Carbon Steel are equivalent to AISI 1075 carbon steel include:
ASTM A29 (1075)
ASTM A510 (1075)
ASTM A713 (1075)
SAE J403 (1075)
SAE J412 (1075)
EN10132 Standard SAE1075 cold rolled carbon steel strip CK75 , C75, C75S Spring steel strip has a carbon content of 0.7-0.8% making it a multi-purpose carbon steel with good spring properties.
Therefore, it is a commonly used carbon steel in a wide range of engineering applications.
C75 Carbon Steel or SAE1075 or CK75 contains 0.7-0.8% carbon, 0.15-0.35% silicon, 0.6-0.9% manganese, and 0.03% phosphorus and sulphur. It has a tensile strength of 1230-1340 MPa, yield strength of 1130-1240 MPa, and a hardness of 57-63 HRC.
CK75 spring steel has better hardenability, the critical hardenable diameter in oil can reach 100~150mm.
CK75 or C75 is Suitable for making very large springs, such as stacked leaf springs on bulldozers, large coil springs and large torsion springs on ships.
CK75 spring steel is a high-carbon steel material. Its chemical composition mainly includes carbon (C) content between 0.70-0.80%, silicon (Si) content between 0.10-0.35%, and manganese (Mn) content between 0.60-0.80%.
Between 0.90%, the contents of phosphorus (P) and sulfur (S) are less than 0.025% respectively.
CK75 spring steel has good elasticity and toughness and is often used to manufacture springs, blades, saw blades, knives and other parts and tools that require high strength and wear resistance.
C75 C75s CK75 SAE 1075 75Cr1 spring steel strip Available in thicknesses from 0.10mm up to 8.0mm and widths up to around 750mm.
1,Delivery Conditions:
| Delivery Condition | Sizes | Surface | Edge |
| 1.Cold Rolled | 1.Thickness: 0.09-8mm | Bright / Polished / Blue/Yellow | Slit |
| 2.Cold Rolled+Hydrogen Annealed | 2.Width: 6-450mm | Round | |
| 3.Cold Rolled+Hardened+Tempered | Coil insider diameter: 300-800mm | Square |
2, Grades comparision:
| GRADES COMPARISON FOR SPRING STEEL | ||||||||
| CHINA GB/T | USA ASTM | JAPAN JIS | GERMANY DIN | FRANCE NF | BIRTAIN BS | ISO | KOREA KS | TAIWAN CNS |
| 45 | 1045 | S45C | CK45 | XC45 | C45 | |||
| 50 | 1050 | S50C | CK50 | XC50 | 080M50 | C50 | ||
| 60 | 1060 | S60C | CK60 | XC60 | 060A62 | C60 | ||
| 70 | 1070 | S70C | CK70 | XS70 | S70 | |||
| 75 | 1075 | S75C | CK75 | XC75 | C75 | |||
| T10 | W1-9 | SK4 | ||||||
| T9 | W1-8 | SK5 | ||||||
| SK85 | — | SK85 | ||||||
| 40Mn | 1043 | SWRH42B | 40Mn4 | 40M5 | 080A40 | SL,SM | ||
| 42Mn | ||||||||
| 65Mn | 1566 | S60C-CSP | CK67 | 080A67 | C60E4 | |||
| 55Si2Mn | 9255 | SUP 6 /SUP7 | 55Si7 | 55Si7 | 251H60 | 55SiCr7 | ||
| 60Si2Mn | 9260 | SUP 6 / SUP7 | 65Si7 | 65Si7 | 251H60 | 61SiCr7 | SUP3 | SUP6 |
| 62Si2Mn | ||||||||
| 75Cr1 | 75Cr1 | 75Cr1 | 75Cr1 | |||||
| 51CrV4 | 5160 | SUP9A | 51CrV4 | 51CrV4 | SPS5A | SUP9A | ||
| 30CrMo | G41300 | SUP13 | 35CrMo4 | SPS9 | SUP13 | |||
| 50CrVA | 6150 | SUP10 | 51CrV4 | 51CrV4 | 735A51 | 51CrV4 | SPS6 | SUP10 |
3,Chemical Composition:
| Standard | Grade | Chemical Composition（%） | ||||||||
| C | Si | Mn | P | S | Cr | Ni | Cu | V | ||
| GB/T699 | 45 | 0.42～0.50 | 0.17～0.37 | 0.50～0.80 | 0.035 | 0.035 | 0.25 | 0.3 | 0.25 | |
| GB/T699 | 50 | 0.47～0.55 | 0.17～0.37 | 0.50～0.80 | 0.035 | 0.035 | 0.25 | 0.3 | 0.25 | |
| GB/T699 | 55 | 0.52～0.60 | 0.17～0.37 | 0.50～0.80 | 0.035 | 0.035 | 0.25 | 0.3 | 0.25 | |
| GB/T699 | 60 | 0.57～0.65 | 0.17～0.37 | 0.50～0.80 | 0.035 | 0.035 | 0.25 | 0.3 | 0.25 | |
| GB/T699 | 65 | 0.62～0.70 | 0.17～0.37 | 0.50～0.80 | 0.035 | 0.035 | 0.25 | 0.3 | 0.25 | |
| GB/T699 | 70 | 0.67～0.75 | 0.17～0.37 | 0.50～0.80 | 0.035 | 0.035 | 0.25 | 0.3 | 0.25 | |
| GB/T699 | 75 | 0.72～0.80 | 0.17～0.37 | 0.50～0.80 | 0.035 | 0.035 | 0.25 | 0.3 | 0.25 | |
| GB/T699 | Mn40 | 0.37～0.44 | 0.17～0.37 | 0.70～1.00 | 0.035 | 0.035 | 0.25 | 0.3 | 0.25 | |
| GB/T699 | Mn45 | 0.42～0.50 | 0.17～0.37 | 0.70～1.00 | 0.035 | 0.035 | 0.25 | 0.3 | 0.25 | |
| GB/T699 | Mn65 | 0.62～0.70 | 0.17～0.37 | 0.90～1.20 | 0.035 | 0.035 | 0.25 | 0.3 | 0.25 | |
| GB/T1298 | SK85/SK5 | 0.80 ~0.90 | ≤0.35 | ≤0.50 | 0.03 | 0.03 | 0.2 | 0.25 | 0.3 | |
| GB/T1298 | SK4 | 0.95～1.04 | ≤0.35 | ≤0.40 | 0.035 | 0.03 | 0.25 | 0.2 | 0.3 | |
| GB/T3077 | 51CrV4 | 0.47～0.55 | 0.17～0.37 | 0.80～1.10 | 0.035 | 0.035 | 0.90～1.20 | 0.3 | 0.3 | 0.10～0.20 |
| GB/T3077 | 50CrVA | 0.47～0.54 | 0.17～0.37 | 0.50～0.80 | 0.025 | 0.025 | 0.80～1.10 | 0.3 | 0.3 | 0.10～0.20 |
| GB/T3077 | 75Cr1 | 0.7～0.8 | 0.25～0.5 | 0.50～0.70 | 0.035 | 0.035 | 0.30～0.40 | |||
| GB/T1222 | 55Si2Mn | 0.52～0.60 | 1.50～2.00 | 0.60～0.90 | ≤0.035 | ≤0.035 | ≤0.35 | ≤0.35 | ≤0.25 | |
| GB/T1222 | 60si2Mn | 0.56～0.64 | 1.50～2.00 | 0.60～0.90 | ≤0.035 | ≤0.035 | ≤0.35 | ≤0.35 | ≤0.25 | |