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Item #:
99843812
4140 Alloy Steel Round Bar, Unpolished (Mill) Finish, Annealed, Cold Finish, ASTM A108, 2.25" Diameter, 24" Length, OnlineMetals
88% of respondents would recommend this to a friend
Item #:
99843812
IMP 685
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What Stands Out
High Strength
The 4140 alloy steel offers exceptional strength and toughness, ideal for demanding applications such as automotive and machinery, outperforming standard steel in durability and reliability.
Precision Dimensions
With a diameter of 0.875 inches and a length of 12 inches, this round bar ensures precise dimensional control, making it perfect for custom fabrication and machine tooling.
Versatile Use
This annealed, cold-finished bar is suitable for various industries, allowing for easy machining and welding, providing flexibility for engineers and manufacturers to innovate freely.
Product Details
| Brand Name | Online Metals |
| Number of Items | 1 |
| Unit Count | 2 Feet |
| Manufacturer | OnlineMetals |
| Model Number | 120538 |
| Part Number | 15475 |
| Item Thickness | 2.25 inches (5.7 cm) |
| Item Weight | 27 pounds (12.25 kg) |
| Item Shape | Round |
| Item Form | Rod |
| Material | Alloy Steel 4140/4142 |
| Grade Rating | 4140 |
| Specification Met | Astm A108 |
| Brand | Online Metals |
| Shape | Round |
Who Should Buy?
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Machinists
Ideal for machinists needing strong, durable materials for precision machining applications in various industries.
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Fabricators
Excellent for fabricators looking for high-strength steel bars for welding and fabrication projects.
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Engineers
Suitable for engineers designing components requiring high wear resistance and toughness in their applications.
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Hobbyists
May not be suitable for casual hobbyists who require lighter materials for simple crafts or projects.
Product Description
4140 Alloy Steel Round Bar, Unpolished (Mill) Finish, Annealed, Cold Finish, ASTM A108, 2.25" Diameter, 24" Length, OnlineMetals
Have any Query? Chat with us
Customer Questions & Answers
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Question:
What are the key properties of the OnlineMetals 4140 Alloy Steel Round Bar?
Answer: The OnlineMetals 4140 Alloy Steel Round Bar is known for its exceptional strength and toughness, which are enhanced by the alloying elements of chromium and molybdenum. The annealed and cold finish processes contribute to its workability, making it ideal for various applications in manufacturing, fabrication, and machining. This round bar's 4140 designation meets the ASTM A108 specifications, ensuring robust performance under demanding conditions, whether you're creating structural components or high-stress machinery parts. -
Question:
What is the difference between annealed and cold finish for steel bars?
Answer: The main difference between annealed and cold finish processes is the treatment applied to the steel. Annealed steel is heated and then cooled slowly, relieving internal stresses and improving ductility. In contrast, cold finish involves cold drawing the metal, resulting in a tighter tolerance, improved surface finish, and slight increase in strength. For projects requiring precise specifications and enhanced surface quality, using annealed and cold finish bars like this one can be vital. -
Question:
What applications are suitable for the 4140 Alloy Steel Round Bar?
Answer: The 4140 Alloy Steel Round Bar is versatile and often used in a variety of applications such as construction, automotive parts, and tool-making. Its strength and fatigue resistance make it ideal for making gears, shafts, and axles. Additionally, it is preferred in heavy-duty applications where durability is essential, like in the manufacturing of heavy machinery and high-load applications. Engineers frequently choose this alloy for its excellent performance in mechanical applications. -
Question:
How does the 2-inch diameter benefit my projects?
Answer: The 2-inch diameter of the OnlineMetals 4140 Alloy Steel Round Bar provides substantial strength and rigidity, which is vital for heavy-duty applications. This size is suitable for creating load-bearing supports and connection components in structural engineering tasks. Additionally, the 2-inch round bar can be effectively machined or welded, making it a flexible option for various project needs, including custom fabrication. -
Question:
Can I machine or weld the 4140 Alloy Steel Round Bar?
Answer: Yes, machining and welding the 4140 Alloy Steel Round Bar is quite feasible due to its post-annealed state. The annealing process enhances its ductility, allowing it to be easily shaped and adjusted with standard machining techniques. When welding, however, proper preheating is recommended to avoid cracking and ensure a strong bond. Applications that involve creating custom fittings or repairing heavy machinery frequently utilize this bar for its adaptability. -
Question:
What are the benefits of unpolished mill finish on this steel bar?
Answer: An unpolished mill finish retains the raw surface texture of the steel, which can be advantageous for certain applications. This finish provides improved adhesion for coatings, paints, or other surface treatments, making it ideal for projects that require subsequent finishing. Additionally, the mill finish may reduce overall costs, as it does not undergo additional processing. Users undertaking construction or welding projects often prefer this finish for its durability. -
Question:
How does ASTM A108 standard apply to the 4140 Alloy Steel Round Bar?
Answer: The ASTM A108 standard covers the specifications for carbon and alloy steel bars that are cold finished. In the case of the 4140 Alloy Steel Round Bar, adherence to this standard means that it maintains strict tolerances and is suitable for most engineering applications requiring high-quality steel. By choosing a product with ASTM A108 compliance, users can ensure that they receive consistent material quality, which is essential for precision engineering. -
Question:
What should I consider when storing the 4140 Alloy Steel Round Bar?
Answer: When storing the 4140 Alloy Steel Round Bar, it’s crucial to keep it in a dry environment to prevent rust and corrosion. Ideally, it should be stored off the ground on pallets or racks to avoid contact with any moisture. Proper inventory management also entails ensuring that the bar is secured and labeled accurately for easy access in future use, especially in workshops or manufacturing settings that frequently utilize this material for fabrication. -
Question:
Is the 4140 Alloy Steel Round Bar available in different lengths?
Answer: Yes, the 4140 Alloy Steel Round Bar is commonly available in various lengths, including standard lengths like 12 feet. Depending on your specific project needs, you can often find custom lengths available to minimize waste and fit your design requirements effectively. This flexibility in length allows for optimal cutting based on your unique manufacturing or construction projects. -
Question:
Where can I buy the OnlineMetals 4140 Alloy Steel Round Bar?
Answer: You can buy the OnlineMetals 4140 Alloy Steel Round Bar from Ubuy, which is a reliable online shopping platform that offers various materials and products tailored to meet your needs. Ubuy provides a user-friendly interface for browsing through specifications of this alloy steel round bar and allows you to order it conveniently from your location in Isle of Man.
Online Metals Rods 120538 Editorial Review
4140 Alloy Steel Round Bar, Unpolished (Mill) Finish, Annealed, Cold Finish, ASTM A108, 2" Diameter, 48" Length, OnlineMetals is an excellent choice for metalworking projects. Crafted from high-quality alloy steel 4140, this 2-inch diameter rod is 4 feet long and weighs 42.7 pounds, making it a sturdy option for tool making and fabrication. Many users have praised its exceptional quality, noting how well it machines on lathes. While a minor shipping error was quickly addressed by the vendor, the overall consensus is that this steel rod performs well, providing reliability for various applications like creating leveling feet or enhancing stability in structures.
Customer Reviews & Ratings
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Pros
- High-quality alloy steel for durability
- Good machining performance on lathes
- Smooth and clean surface finish
- Perfect for tool making and fabrication
- Great for structural stability projects
Cons
- Slightly bent upon arrival, but manageable
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IMP 685
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