STKR490 and STKR400 are two main steel grades under the JIS G 3466 standard. Their main differences lie in their mechanical properties and chemical compositions, which affect their applications and performance. Here is a comparison between the two:
| STKR490 | STKR400 | ||
| Chemical Composition | Carbon (C) | ≤0.18% | ≤0.25% |
| Silicon (Si) | ≤0.55% | no specify the maximum content of these elements | |
| Manganese (Mn) | ≤1.5% | no specify the maximum content of these elements | |
| Phosphorus (P) | ≤ 0.04% | ≤ 0.04% | |
| Sulfur (S) | ≤ 0.04% | ≤ 0.04% | |
| Mechanical Properties | Tensile Strength | ≥490 MPa | ≥400 MPa |
| Yield Point or Proof Stress | ≥325 MPa | ≥245 MPa | |
| Elongation | ≥23% | ≥23% | |
Applications:
STKR400:
- Used for general structural purposes.
- Suitable for applications where moderate strength is sufficient.
- Commonly used in construction and structural applications that do not require high strength.
STKR490:
- Used for applications requiring higher strength.
- Suitable for structural components that need to bear higher loads.
- Often used in construction, engineering structures, and other applications where higher mechanical performance is needed.
Performance:
STKR490 offers better performance in terms of strength and durability, but it may be less formable and more difficult to weld compared to STKR400.
STKR400 offers a good balance of strength and formability, making it easier to work with in a variety of construction and fabrication processes.
These differences in mechanical properties and chemical composition make STKR490 has higher tensile strength and yield strength compared to STKR400, making it suitable for applications that require higher load-bearing capabilities. Additionally, STKR490 contains more alloying elements such as silicon and manganese in its chemical composition, which may contribute to its enhanced performance. STKR400, with its broader range of applications and lower strength requirements, is used for general structural purposes. The choice between these two steel grades will depend on specific engineering requirements and performance needs.
