AK Steel ASTM A 1018, Grade 33 Hot Rolled Carbon Steel, Structural Steel (SS)

AK Steel ASTM A 1018, Grade 33 Hot Rolled Carbon Steel, Structural Steel (SS) Product Information -:- For detailed product information, please contact sales. -: AK Steel ASTM A 1018, Grade 33 Hot Rolled Carbon Steel, Structural Steel (SS) Synonyms -:- For detailed product information, please contact sales. -:

AK Steel ASTM A 1018, Grade 33 Hot Rolled Carbon Steel, Structural Steel (SS) Product Information -:- For detailed product information, please contact sales. -: **Product Name:** AK Steel ASTM A1018, Grade 33 Hot-Rolled Carbon Steel, Structural Steel (SS) --- ### **1. Overview** AK Steel's ASTM A1018 Grade 33 is a hot-rolled carbon steel sheet and strip that has undergone a mandatory **normalization or controlled cooling process**. This post-rolling heat treatment differentiates it from the more common ASTM A1011 grades, resulting in a steel with **enhanced and more uniform mechanical properties, superior notch toughness, and improved internal soundness**. With a minimum yield strength of 33 ksi (230 MPa), it is engineered for structural and pressure vessel applications where material consistency, reliability, and predictable performance under stress are more critical than base cost. It is a preferred choice for code-governed constructions and demanding fabrications. --- ### **2. International Standards** This product is manufactured to meet the exacting requirements of the following standard, which mandates specific processing for property enhancement: * **ASTM A1018 / A1018M:** Standard Specification for Steel, Sheet and Strip, Heavy-Thickness Coils, Hot-Rolled, Carbon, Commercial, Drawing, Structural, High-Strength Low-Alloy, and High-Strength Low-Alloy with Improved Formability, Grade 33. * The standard requires **normalizing** or an equivalent controlled processing to achieve a refined grain structure. It is also designed to cover **heavier thickness coils** than typical sheet specifications, ensuring property consistency in thicker gauges. --- ### **3. Chemical Composition (Typical, % by Weight)** The chemistry is balanced to achieve the specified strength and to respond favorably to the normalization heat treatment, ensuring through-thickness homogeneity. | Element | Content (Maximum, unless specified) | Role & Implication | | :--- | :--- | :--- | | **Carbon (C)** | 0.18% - 0.25% (Typical range) | Provides fundamental strength. Controlled to ensure good weldability and a positive response to normalization. | | **Manganese (Mn)** | 0.70% - 0.90% | Primary strengthening element; promotes hardenability and aids in achieving a fine-grained microstructure after normalization. | | **Phosphorus (P)** | 0.035% max | Residual impurity; minimized for improved ductility and notch toughness. | | **Sulfur (S)** | 0.035% max | Residual impurity; controlled to enhance weldability and transverse properties. | | **Silicon (Si)** | 0.10% - 0.30% | Acts as a deoxidizer (killed steel practice); contributes to strength. | | **Aluminum (Al)** | May be present (typically for grain refinement) | Used in killed steel to control initial austenite grain size, which is further refined during normalization. | | **Key Process:** | **Normalized.** The steel is reheated to above its critical temperature and cooled in air. This process refines the grain structure, homogenizes the microstructure, and relieves internal stresses from rolling, leading to superior and consistent properties. | | --- ### **4. Physical & Mechanical Properties** Properties are guaranteed in the normalized condition, offering significant advantages over as-rolled steels in terms of consistency and toughness. | Property | Specification Minimum (ASTM A1018 Grade 33) | Typical Value / Description | | :--- | :--- | :--- | | **Yield Strength (min)** | 33 ksi (230 MPa) | Consistent through the thickness of the material. | | **Tensile Strength** | 49 ksi min (340 MPa) | Typically ranges from 49 - 65 ksi (340 - 450 MPa). | | **Elongation in 2" (min)** | 22% (for thickness ≥ 0.23 in.) | Good ductility, enhanced by the refined, uniform grain structure. | | **Key Distinguishing Property** | **Superior Notch Toughness** | The normalized, fine-grained ferrite-pearlite microstructure provides significantly better impact resistance (Charpy V-Notch values) and a lower ductile-to-brittle transition temperature compared to as-rolled grades like A1011 Grade 33. This is often a specified requirement. | | **Microstructure** | Uniform, fine-grained ferrite-pearlite | Result of the normalization process, ensuring isotropic properties (similar in all directions). | | **Surface Finish** | Standard hot-rolled mill finish. | The scale may be more uniform due to controlled cooling. | --- ### **5. Key Features & Advantages** * **Guaranteed Toughness & Homogeneity:** The mandatory normalization process is the core benefit, delivering reliable, uniform mechanical properties and exceptional resistance to brittle fracture. This is paramount for safety in pressure vessels and dynamically loaded structures. * **Excellent Weldability with Stable HAZ:** The refined and homogeneous base metal microstructure leads to a more predictable and tougher heat-affected zone (HAZ) after welding, reducing the risk of defects. * **Isotropic Forming Characteristics:** Properties are consistent in all directions (longitudinal and transverse), providing predictable behavior during bending, rolling, and other forming operations. * **Ideal for Heavier Sections:** ASTM A1018 is intended for heavier gage coils. Normalization ensures property uniformity throughout thick sections, where rolling effects can cause property gradients in as-rolled material. * **Code-Compliant Material:** Routinely specified in ASME Boiler and Pressure Vessel Code (BPVC) and other structural codes where normalized material is required or preferred for its proven performance. --- ### **6. Product Applications** ASTM A1018 Grade 33 is specified for applications where material integrity, consistency, and toughness are design priorities. * **Pressure Vessels & Boilers:** Shells, heads, and major components for low to moderate-pressure service where construction codes (e.g., ASME Section VIII, Div. 1) often call for normalized steels. * **Structural Applications Requiring Toughness:** Support structures, crane runways, and building frames in environments subject to dynamic loads, vibration, or lower service temperatures. * **Heavy Machinery & Equipment:** Critical frames, weldments, and bases for industrial, mining, and agricultural machinery that demand reliable performance under stress. * **Storage Tanks & Silos:** Fabrication of tanks for bulk storage of liquids or solids where consistent material properties ensure structural reliability. * **General Fabrication (High-Reliability):** Used when the engineering specification calls for normalized steel to eliminate variability and ensure part-to-part consistency, especially in thicker materials. --- ### **7. Fabrication & Processing Notes** * **Descaling:** Mill scale must be removed via pickling or abrasive blasting prior to welding or high-quality painting. * **Forming:** Excellent for cold bending and forming. The normalized condition provides consistent yield strength and predictable springback. * **Welding:** Highly weldable using all standard processes (SMAW, GMAW, FCAW). No preheat is typically required for common thicknesses. Use of low-hydrogen practices is always recommended for optimal results. * **Post-Weld Heat Treatment (PWHT):** Often **not required** for this grade after welding, as the base metal is already in a stable, stress-relieved condition. PWHT may be specified by governing codes for very thick sections or specific service conditions (e.g., lethal service). * **Machining:** The uniform hardness resulting from normalization allows for consistent and good machinability. --- **Disclaimer:** *This profile is a technical summary. AK Steel is now part of Cleveland-Cliffs Inc.* For engineering and procurement, always consult the latest official **ASTM A1018** standard and the certified **Mill Test Report (MTR)** from the manufacturer. The MTR is crucial as it certifies the material as normalized and provides the actual chemistry, mechanical properties, and often impact test results. This grade is typically specified by **ASTM designation and grade**, not by generic name. -:- For detailed product information, please contact sales. -: AK Steel ASTM A 1018, Grade 33 Hot Rolled Carbon Steel, Structural Steel (SS) Specification Dimensions Size： Diameter 20-1000 mm Length <4590 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 1018, Grade 33 Hot Rolled Carbon Steel, Structural Steel (SS) Properties -:- For detailed product information, please contact sales. -:

Applications of AK Steel ASTM A 1018, Grade 33 Hot Rolled Carbon Steel, Structural Steel (SS) -:- For detailed product information, please contact sales. -: Chemical Identifiers AK Steel ASTM A 1018, Grade 33 Hot Rolled Carbon Steel, Structural Steel (SS) -:- For detailed product information, please contact sales. -:

Packing of AK Steel ASTM A 1018, Grade 33 Hot Rolled Carbon Steel, Structural Steel (SS) -:- 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 1061 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