Low Alloy Z Direction Steel Plates are engineered to resist lamellar tearing in welded joints while providing excellent structural performance. Designed for offshore structures, bridges, industrial facilities, and medium-thickness construction projects, these plates ensure through-thickness ductility (Z-direction) required for safe welding and long-term durability.
Our Low Alloy Z Plates include a wide range of grades such as Q345B, Q345D, Q355B, Q390B, and other international equivalents, with Z-grade options Z15, Z25, and Z35, providing flexibility for a variety of projects.
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Low Alloy Z Direction Steel Plate We Supply
Low Alloy Z Direction Steel Plates are ideal for medium-thickness structural projects where weld-induced stresses can cause lamellar tearing in ordinary steel plates. By controlling chemical composition and production processes, these plates deliver:
High Z-direction ductility (through-thickness toughness)
Excellent weldability and performance in thick welded joints
Consistent mechanical properties for structural reliability
Typical Low Alloy Grades & Z Ratings:
| Material Grade | Z-Grade | Thickness Range (mm) | Z-Direction RA (%) | Yield Strength (MPa) | Tensile Strength (MPa) |
|---|---|---|---|---|---|
| Q345B | Z15 | 6–20 | ≥15% | 345 | 470–600 |
| Q345B | Z25 | 6–40 | ≥25% | 345 | 470–600 |
| Q345B | Z35 | 20–50 | ≥35% | 345 | 470–600 |
| Q345D | Z15 | 6–20 | ≥15% | 345 | 470–600 |
| Q355B | Z15 | 6–20 | ≥15% | 355 | 490–630 |
| Q355B | Z25 | 6–40 | ≥25% | 355 | 490–630 |
| Q355B | Z35 | 20–50 | ≥35% | 355 | 490–630 |
| Q390B | Z15 | 6–25 | ≥15% | 390 | 520–620 |
| Q390B | Z25 | 6–40 | ≥25% | 390 | 520–620 |
⚠️ Note: Other equivalent low alloy grades can be supplied upon request. Contact us for project-specific recommendations.
Low Alloy Z Direction Steel Plate Applications
Low Alloy Z Direction Steel Plates are widely used in medium-thickness welded structures where high Z-direction ductility is critical:
Bridges – Girders, stiffeners, and deck plates
Shipbuilding – Decks, hull structures, and offshore platforms
Industrial Facilities – Medium-thickness structural frames, pressure vessels
General Construction – Medium-thickness structural steel where welding safety is required
Z-Grade Selection Guide
Choosing the correct Z-grade is critical to avoid lamellar tearing and optimize costs.
| Z-Grade | Recommended Application | Key Advantage |
|---|---|---|
| Z15 | Light to medium-thickness structures | Cost-effective, safe for thinner plates |
| Z25 | Medium-thickness welded joints | Higher ductility, suitable for bridges & ships |
| Z35 | Thick welded joints & heavy load areas | Maximum lamellar tearing resistance, ideal for offshore and bridge heavy sections |
Pro Tip: Always match Z-grade with thickness and welding process to ensure maximum safety and performance. Our engineers can provide guidance for your project.
Technical Compliance
Standards: EN 10164, ASTM A516/A572 equivalents
Certifications: Mill Test Certificates (MTC), Third-Party Testing
Welding & Fabrication: Suitable for all conventional welding methods with proper preheat & post-weld heat treatment if required
FAQ – Low Alloy Z Direction Steel Plate Products
What is the difference between Low Alloy Z Direction Steel Plates and High Strength Z Direction Steel Plates?
Low Alloy Z Direction Plates provide medium yield strength (345–355 MPa) and are suited for medium-thickness applications, while High Strength Z Direction Plates (≥420 MPa) are used for heavy load structures.
How do I choose between Z15, Z25, and Z35?
The choice depends on plate thickness, welded joint type, and project requirements. Z35 is recommended for thick plates and offshore or bridge structures.
Are Low Alloy Z Plates available in custom thickness and size?
Yes, we provide cutting to your specifications. Contact us for size, thickness, and project guidance.
Request a Quote for Low Alloy Z Direction Steel Plate Today
Ensure your project avoids lamellar tearing and unnecessary costs.
Fill out your inquiry with:
Material grade (Q345B, Q355B, Q390B, or other)
Z-grade (Z15, Z25, Z35)
Plate thickness & quantity
Application / Project type
Delivery port
Our engineers will provide a detailed technical recommendation and competitive quotation within 24 hours.
⚡ Get the right Low Alloy Z Direction Steel Plate for your project today!