1. Tensile Strength Range
Typical Values:
270-350 MPa (according to standards such as EN 10346 and JIS G 3302).
Specific values vary slightly depending on the manufacturer, zinc layer thickness, and annealing process.
Relationship with Other Properties:
Because DX57D emphasizes high ductility (deep drawing performance), its tensile strength is generally low, placing it in the soft steel category.
Yield strength (YS) is typically 140-260 MPa, and elongation (A80) is ≥30%.
2. Standard Comparison
Standard Grade Tensile Strength (MPa) Yield Strength (MPa) Elongation (%)
EN 10346 DX57D+Z 270-350 140-260 ≥30
JIS G 3302 SGCC (similar) 270-380 120-260 ≥30
GB/T 2518 DC57D+Z 270-350 140-260 ≥30
3. Factors Affecting Tensile Strength
Base Material Composition: Low carbon (C ≤ 0.12%) and low alloying elements (e.g., Mn and P) ensure soft properties.
Galvanizing Process: Hot-dip galvanizing (+Z) has little effect on base material strength, but high-temperature annealing may slightly reduce strength.
Cold Rolling Deformation: Adjustments to the rolling process can fine-tune strength (e.g., by controlling the reduction ratio).
4. Strength Considerations in Applications
Application Scenarios:
Low tensile strength → Suitable for high-deformation processes (such as deep drawing and stretching), but not suitable for load-bearing structural parts.
If higher strength is required, DX58D+Z (340-420 MPa) or HX340LAD+Z (high-strength steel) can be selected.
Corrosion protection and strength balance: The thickness of the zinc coating (such as Z60/Z80) does not affect tensile strength, but increasing the coating may affect subsequent formability.
5. Frequently Asked Questions
Q: Does a tensile strength below 300 MPa meet the standard?
Yes, the core performance of DX57D+Z is formability, not strength. If the customer requires higher strength, a different grade is required.
Q: How is tensile strength tested?
Tensile testing is performed on transverse or longitudinal specimens according to ISO 6892-1 or ASTM A370.
Q: What is the strength difference compared to DX54D+Z?
DX54D+Z has a similar tensile strength range (270-350 MPa), but slightly lower elongation (≥26%) and inferior deep drawability.
6. Material Selection Recommendations
Prioritizing tensile strength → Choose a higher grade (such as DX58D+Z or the HX series).
Prioritizing formability → DX57D+Z is an ideal choice, also offering galvanized corrosion protection.