ASTM A871 HSLA Steel Grade 65, Hot-Rolled

ASTM A871 HSLA Steel Grade 65, Hot-Rolled, 5-20 mm (3/16 to 3/4 in.) Product Information -:- For detailed product information, please contact sales. -: ASTM A871 HSLA Steel Grade 65, Hot-Rolled, 5-20 mm (3/16 to 3/4 in.) Synonyms -:- For detailed product information, please contact sales. -:

ASTM A871 HSLA Steel Grade 65, Hot-Rolled, 5-20 mm (3/16 to 3/4 in.) Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: ASTM A871 Grade 65 High-Strength Low-Alloy (HSLA) Steel** **ASTM A871 Grade 65** is a **hot-rolled, high-strength, low-alloy structural steel** specifically engineered to deliver **higher strength combined with improved atmospheric corrosion resistance**. Designed for the **lighter gauge range of 5-20 mm (3/16 to 3/4 in.)**, this grade provides a **minimum yield strength of 65 ksi (450 MPa)** while maintaining **corrosion resistance approximately twice that of plain carbon steel with similar copper content**. Supplied in the hot-rolled condition, it utilizes a balanced alloy system to achieve enhanced mechanical properties without requiring post-rolling heat treatment, making it ideal for weight-sensitive structural components where durability and strength are prioritized. --- ## **International Standard & Key Specifications** * **Primary Standard:** **ASTM A871/A871M** - Standard Specification for High-Strength Low-Alloy Structural Steel Plate With Improved Atmospheric Corrosion Resistance. * **Grade Variants:** Available as **Grade 65** and **Grade 65SX**. The **"SX" designation** indicates steel produced with improved sulfide shape control, enhancing through-thickness (Z-direction) ductility and resistance to lamellar tearing in critical welded joints. * **Governing Standard:** **ASTM A6/A6M** - Standard Specification for General Requirements for Rolled Structural Steel Bars, Plates, Shapes, and Sheet Piling. * **Related Specifications:** * **ASTM A709/A709M** - Structural Steel for Bridges (for comparable higher-strength applications). * **AWS D1.1** - Structural Welding Code – Steel. * **Condition:** Supplied exclusively in the **hot-rolled condition**. --- ## **Chemical Composition (Weight %, max unless range is specified) - Grade 65** The composition is optimized to achieve 65 ksi yield strength while ensuring good weldability and the specified atmospheric corrosion resistance. | Element | Composition (%) | Role in Performance | | :--- | :--- | :--- | | **Carbon (C)** | 0.23 max | Provides foundational strength; controlled to manage weldability. | | **Manganese (Mn)** | 1.35 max | Primary solid-solution strengthener; critical for achieving the higher yield strength. | | **Phosphorus (P)** | 0.04 max | Contributes to atmospheric corrosion resistance. | | **Sulfur (S)** | 0.05 max (Standard & SX)* | Impurity. In SX grades, metallurgical treatment modifies sulfide inclusion morphology to improve Z-direction properties. | | **Silicon (Si)** | 0.30 max | Deoxidizer and solid solution strengthener. | | **Copper (Cu)** | **0.20 min** | **Essential alloying element.** Provides the fundamental improvement in atmospheric corrosion resistance. | | **Chromium (Cr)** | 0.40 - 0.70 | Enhances atmospheric corrosion resistance and may contribute to hardenability. | | **Nickel (Ni)** | 0.40 max | May be present to enhance toughness. | | **Vanadium (V)** | 0.02 - 0.15 (typical) | Key microalloy for precipitation strengthening, vital for reaching the 65 ksi strength level. | | **Columbium (Cb/Nb)** | 0.005 - 0.05 (optional) | Microalloy for grain refinement. | *Note for SX Grade:* The distinguishing feature is **sulfide shape control** (e.g., via calcium treatment), which transforms elongated MnS inclusions into more globular forms, significantly improving ductility in the short transverse direction. --- ## **Typical Physical & Mechanical Properties (Hot-Rolled, Thickness 5-20 mm / 3/16 to 3/4 in.)** Properties are guaranteed for hot-rolled material within this specific, lighter thickness range. | Property | Value / Description | | :--- | :--- | | **Tensile Strength** | 550 - 725 MPa (80,000 - 105,000 psi) | | **Yield Strength (min)** | **450 MPa (65,000 psi)** | | **Elongation in 2-in (50 mm) (min)** | 17% | | **Modulus of Elasticity** | ~200 GPa (29 x 10⁶ psi) | | **Density** | ~7.85 g/cm³ (0.284 lb/in³) | | **Charpy V-Notch Impact Toughness** | Not a default requirement of the base specification but can be specified via supplementary requirements for low-temperature service (e.g., testing at 0°F / -18°C or -40°F / -40°C). | | **Atmospheric Corrosion Resistance** | Approximately **2 times** greater than plain carbon steel in similar environments. | | **Through-Thickness (Z-Direction) Ductility** | **Standard Grade:** Adequate for most applications. **SX Grade:** **Superior** resistance to lamellar tearing, recommended for highly restrained T, K, and corner joints. | --- ## **Product Applications** ASTM A871 Grade 65 is specified for structural applications where maximizing strength-to-weight ratio is critical, and where enhanced atmospheric durability adds value, particularly in medium-duty to heavy-duty components. **Primary Industries and Products:** 1. **Transportation & Heavy Equipment:** * **Chassis frames, crossmembers, and subframes** for high-performance heavy-duty trucks, buses, and specialty vehicles. * **Boom arms, lift components, and structural members** for construction and agricultural machinery. * **Railcar underframes and structural components**. 2. **Material Handling & Storage:** * **High-capacity storage rack systems** (uprights and beams for heavy loads). * **Forklift masts** and **crane components**. * **Heavy-duty industrial platforms** and **work access structures**. 3. **Structural & Construction:** * **Lightweight truss members** and **bracing** for buildings and structures. * **Supporting structures** for heavy mechanical equipment. * **Components in mobile and modular structures**. 4. **Infrastructure:** * **High-strength components** for signage, lighting, and signal supports. --- ## **Advantages and Critical Fabrication Considerations** * **Advantages:** * **High Strength-to-Weight Ratio:** 65 ksi yield strength enables significant weight reduction and material efficiency in structural designs. * **Enhanced Durability:** Provides a tangible improvement in corrosion resistance over standard high-strength steels, extending the service life of painted components. * **Fabrication-Friendly:** Good weldability and formability for its strength level in the hot-rolled condition. * **Specialized SX Grade:** Offers a direct solution to prevent lamellar tearing in critical, thick-welded assemblies, even in thinner plates. * **Critical Fabrication Considerations:** * **Welding:** Due to the higher strength and alloy content, **strict low-hydrogen welding procedures are strongly recommended.** Preheat (150-250°F / 65-120°C) is often advisable, especially for the upper end of the thickness range and restrained joints. Welding consumables should match the strength (e.g., E8018 series). * **Corrosion Performance Clarification:** This steel is **not equivalent to ASTM A588 weathering steel**. Its corrosion resistance is an **enhancement for painted systems** or for use in mild environments. It will not form a stable, protective patina like dedicated weathering steels. * **Forming:** While formable, the higher strength results in greater springback and requires more force. Minimum bend radii are larger than for mild steel (typically ≥ 3x thickness for 90-degree bends across the grain). * **Thermal Effects:** Hot-dip galvanizing after fabrication may lead to some loss of yield strength due to the thermal cycle. If galvanizing is required, the potential for property alteration should be evaluated and tested. * **Grade Selection:** For fabrication involving highly restrained welds (e.g., intersecting plates), specifying the **65SX grade** is a prudent engineering decision to mitigate the risk of through-thickness cracking. **In summary, ASTM A871 Grade 65 is a high-performance HSLA steel offering an excellent balance of 65 ksi yield strength and improved atmospheric corrosion resistance in a hot-rolled, readily fabricable form. It is ideally suited for demanding applications in transportation and material handling equipment where reducing weight without compromising durability is a key design objective. The availability of the SX grade provides an additional layer of reliability for critical welded structures.** -:- For detailed product information, please contact sales. -: ASTM A871 HSLA Steel Grade 65, Hot-Rolled, 5-20 mm (3/16 to 3/4 in.) Specification Dimensions Size： Diameter 20-1000 mm Length <4551 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. -: ASTM A871 HSLA Steel Grade 65, Hot-Rolled, 5-20 mm (3/16 to 3/4 in.) Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A871 HSLA Steel Grade 65, Hot-Rolled, 5-20 mm (3/16 to 3/4 in.) -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A871 HSLA Steel Grade 65, Hot-Rolled, 5-20 mm (3/16 to 3/4 in.) -:- For detailed product information, please contact sales. -:

Packing of ASTM A871 HSLA Steel Grade 65, Hot-Rolled, 5-20 mm (3/16 to 3/4 in.) -:- 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 1022 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