AK Steel ASTM A 570, Grade 33 Hot Rolled Carbon Steel

AK Steel ASTM A 570, Grade 33 Hot Rolled Carbon Steel, Structural Quality (SQ) Product Information -:- For detailed product information, please contact sales. -: AK Steel ASTM A 570, Grade 33 Hot Rolled Carbon Steel, Structural Quality (SQ) Synonyms -:- For detailed product information, please contact sales. -:

AK Steel ASTM A 570, Grade 33 Hot Rolled Carbon Steel, Structural Quality (SQ) Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: AK Steel ASTM A570 Grade 33 (SQ) Hot Rolled Carbon Steel** **AK Steel ASTM A570 Grade 33 (Structural Quality - SQ)** is a **general-purpose, hot-rolled carbon steel sheet and strip** offering a slightly higher strength level within the versatile A570 series. Designed for **structural and fabricated components requiring basic strength and excellent formability**, this grade provides a **minimum yield strength of 33 ksi (230 MPa)**. The "SQ" designation confirms its production to standard **Structural Quality** requirements, making it a cost-effective and readily available choice for a broad range of commercial, industrial, and light structural applications where weldability and ease of fabrication are paramount. --- ## **International Standard & Key Specifications** * **Primary Standard:** **ASTM A570/A570M** - Standard Specification for Steel, Sheet and Strip, Carbon, Hot-Rolled, Structural Quality. * **Quality Designation:** **Structural Quality (SQ)** - Denotes standard commercial quality suitable for structural uses without special hardening or aging properties. * **Governance:** Produced to standard mill practices for hot-rolled products. Dimensional tolerances are often referenced to **ASTM A568**. * **Related Standards:** * **SAE J1392** - Hot Rolled HSLA and Carbon Steel Sheet and Strip. * **ASTM A1011** - Standard Specification for Steel, Sheet and Strip, Hot-Rolled, Carbon, Structural, High-Strength Low-Alloy and High-Strength Low-Alloy with Improved Formability. * **Key Distinction:** A **basic carbon-manganese steel** without intentional alloying elements like vanadium or niobium, differentiating it from higher-strength, microalloyed HSLA grades. --- ## **Chemical Composition (Weight %, max)** The composition is characteristic of standard hot-rolled carbon steel, with carbon and manganese providing the primary strength. | Element | Composition (%) | Role in Performance | | :--- | :--- | :--- | | **Carbon (C)** | 0.25 max | Primary strengthener; controlled to balance strength with formability and weldability. | | **Manganese (Mn)** | 0.90 max | Enhances strength and hardenability; complements carbon's effect. | | **Phosphorus (P)** | 0.04 max | Impurity, kept low for good formability and weldability. | | **Sulfur (S)** | 0.05 max | Impurity, controlled to minimize hot shortness. | | **Silicon (Si)** | - (Residual) | Deoxidizer; typically present in small amounts from steelmaking. | | **Carbon Equivalent (CE)** | ~0.35 - 0.42 | Moderate, indicating good weldability with standard procedures. | **Note:** Actual mill chemistry will vary within these maximum limits to achieve the specified mechanical properties and optimize rolling performance. It is a commodity-grade steel. --- ## **Typical Physical & Mechanical Properties (Hot-Rolled, Grade 33)** | Property | Value / Description | | :--- | :--- | | **Tensile Strength** | 360 - 500 MPa (52,000 - 73,000 psi) | | **Yield Strength (min)** | **230 MPa (33,000 psi)** | | **Elongation in 2-in (50 mm) (min)** | **24%** (High elongation indicates excellent ductility and formability). | | **Modulus of Elasticity** | ~200 GPa (29 x 10⁶ psi) | | **Density** | ~7.85 g/cm³ (0.284 lb/in³) | | **Formability** | **Excellent.** Suitable for moderate to severe bending, roll forming, and stamping operations. Minimum bend radius is typically **0.5 x material thickness** for a 90° bend. | | **Weldability** | **Very Good.** Easily welded using all common processes (SMAW, GMAW, GTAW, Resistance Welding). Preheating is generally not required for typical gauges. | --- ## **Product Applications** AK Steel A570 Grade 33 (SQ) is employed in a wide variety of applications that benefit from its slightly higher strength than Grade 30, while maintaining excellent fabricability. **Primary Industries and Products:** 1. **Light Structural Framing & Building Components:** * **Purlins, girts, and light structural members** in pre-engineered metal buildings. * **Studs, tracks, and framing** for non-load bearing walls. * **Guardrails, fencing, and architectural trim.** 2. **Fabricated Enclosures & Cabinets:** * **Electrical cabinets, control boxes, and switchgear enclosures.** * **HVAC ductwork, plenums, and fittings.** * **Machine guards, covers, and shields.** 3. **Transportation & Automotive:** * **Internal structural components** for truck bodies, trailers, and RV frames. * **Flooring, partitions, and interior supports.** * **Brackets and mounts** for agricultural equipment. 4. **Material Handling & Storage:** * **Industrial shelving, racks, and lockers.** * **Pallets, skids, and material handling containers.** 5. **General Manufacturing & Stampings:** * **Base plates, brackets, and mounting hardware.** * **Stamped components** for various appliances and fixtures. --- ## **Advantages and Fabrication Considerations** * **Advantages:** * **Cost-Effective Strength:** Provides a modest increase in yield strength over Grade 30 at a minimal premium, offering better value for strength-limited designs. * **Excellent Formability:** High elongation allows for successful bending and forming into complex shapes. * **Superior Weldability:** Readily welded with minimal special preparation or procedures. * **High Availability:** A standard stock item at most steel service centers and distributors. * **Fabrication Considerations:** * **Surface Condition:** Hot-rolled material has a characteristic mill scale. For painting or galvanizing, this scale must be removed via pickling, abrasive blasting, or grinding. The **"Pickled and Oiled" (P&O)** condition is commonly specified for a clean, paintable surface. * **Flatness:** May exhibit minor camber or edge wave; leveling may be required for precision fabrication. * **Strain Aging:** Like many low-carbon steels, it may be susceptible to strain aging after cold working, which can slightly increase yield strength and decrease ductility over time. * **Application Limits:** Not intended for high-stress, fracture-critical, or primary load-bearing structural applications. For such uses, specified structural steels like **ASTM A36** (plate) or **ASTM A992** (shapes) are more appropriate. * **Corrosion Protection:** Requires protective coatings (paint, galvanizing) for long-term service in corrosive environments. **In summary, AK Steel ASTM A570 Grade 33 (SQ) is a practical and economical hot-rolled carbon steel that delivers a balanced profile of slightly elevated strength, excellent formability, and easy weldability. It serves as a reliable material for a vast array of light structural and general fabrication projects where performance, cost, and manufacturability are key considerations.** -:- For detailed product information, please contact sales. -: AK Steel ASTM A 570, Grade 33 Hot Rolled Carbon Steel, Structural Quality (SQ) Specification Dimensions Size： Diameter 20-1000 mm Length <4555 mm Size:We can customized as required Standard： Per your request or drawing We can customized as required Properties（Theoretical） Chemical Composition -:- For detailed product information, please contact sales. -: AK Steel ASTM A 570, Grade 33 Hot Rolled Carbon Steel, Structural Quality (SQ) Properties -:- For detailed product information, please contact sales. -:

Applications of AK Steel ASTM A 570, Grade 33 Hot Rolled Carbon Steel, Structural Quality (SQ) -:- For detailed product information, please contact sales. -: Chemical Identifiers AK Steel ASTM A 570, Grade 33 Hot Rolled Carbon Steel, Structural Quality (SQ) -:- For detailed product information, please contact sales. -:

Packing of AK Steel ASTM A 570, Grade 33 Hot Rolled Carbon Steel, Structural Quality (SQ) -:- For detailed product information, please contact sales. -: Standard Packing: -:- For detailed product information, please contact sales. -: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 1026 gallon liquid totes Special package is available on request. E FORUs’ is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition