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Item #:
99843812
4140 Alloy Steel Round Bar, Unpolished (Mill) Finish, Annealed, Cold Finish, ASTM A108, 0.75" Diameter, 36" Length, OnlineMetals
Item #:
99843812
USD 303
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Imported from USA store
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Order now and get it around Sunday, August 09
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4140 steel, also known as 'Chromoly Steel', is renowned for its strength and resistance to fracturing in high-stress applications.
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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
| Item Diameter | 0.75 Inches (1.9 cm) |
| Item Thickness | 0.75 Inches (1.9 cm) |
| Item Weight | 0.01 Ounces (0.28 grams) |
| Color | Silver |
| Item Shape | Round |
| Item Form | Rod |
| Material | Alloy Steel 4140/4142 |
| Grade Rating | 4140 |
| Specification Met | Astm A108 |
| Brand Name | Online Metals |
| Number of Items | 1 |
| Model Number | 120602 |
| Part Number | 15488 |
| Unit Count | 3.0 Feet |
| Manufacturer | OnlineMetals |
| 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, 0.75" Diameter, 36" Length, OnlineMetals
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Customer Questions & Answers
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Question:
What is 4140 Alloy Steel and what are its key properties?
Answer: 4140 Alloy Steel is a versatile steel alloy that contains chromium, molybdenum, and manganese, providing excellent hardness, strength, and wear resistance. This makes it ideal for applications requiring toughness and durability. The annealed condition of this steel further enhances its machinability and reduces internal stresses, making it easier to work with. It's commonly used in manufacturing components like gears, crankshafts, and heavy-duty machinery parts due to its high tensile strength and impact resistance. -
Question:
What applications are suitable for a 2.25-inch diameter steel round bar?
Answer: A 2.25-inch diameter steel round bar is suitable for various industrial applications, including construction, automotive, and aerospace industries. Its significant diameter allows it to be used in high-stress environments, such as making custom shafts, structural supports, and heavy-duty tooling. Additionally, its cold finish enhances its surface quality, which is beneficial for precision machining and fabrication tasks where tight tolerances are required. -
Question:
How does the annealing process affect the properties of the 4140 steel bar?
Answer: The annealing process involves heating the steel to a specified temperature and then gradually cooling it to alter its microstructure. For 4140 steel, this reduces hardness and increases ductility, making it more workable for machining processes. Annealed steel is less prone to cracking or breaking under stress, making it ideal for parts that will undergo significant mechanical loads or alterations. The improved ductility means that the bar can be shaped or formed into intricate components with reduced risk of fracturing. -
Question:
What does unpolished mill finish mean for the 4140 steel round bar?
Answer: An unpolished mill finish refers to the surface condition of the steel bar directly from the manufacturing process. This finish retains a rougher texture, showing visible scale or mill marks typical of products that haven’t undergone additional processing like polishing or grinding. While it may not be aesthetically pleasing, this surface condition is effective for functions where surface appearance is less critical, such as structural applications or when further machining will be done to achieve the desired finish. -
Question:
Is 4140 Alloy Steel resistant to corrosion?
Answer: While 4140 Alloy Steel is known for its strength, it is not inherently corrosion-resistant. The alloy contains chromium which provides some level of resistance against oxidation, but it is not comparable to stainless steel. For applications exposed to harsh environments or moisture, it's advisable to apply protective coatings or to use stainless steel options. Proper maintenance and applying coatings can help increase its lifespan in corrosive conditions, making it suitable for parts that might face challenging operational settings. -
Question:
Can the 4140 alloy round bar be heat treated?
Answer: Yes, the 4140 alloy round bar can be heat treated to enhance its mechanical properties further. Heat treatment processes such as quenching and tempering allow it to achieve different levels of hardness and strength tailored to specific applications. For instance, quenching can increase hardness significantly, making it suitable for heavy-duty applications, while tempering can reduce brittleness, ensuring a balance between hardness and toughness. This versatility in heat treatment options makes 4140 a popular choice in custom engineering projects. -
Question:
What are the advantages of using Cold Finished steel over Hot Finished?
Answer: Cold Finished steel offers several advantages over hot finished steel, including improved dimensional precision, enhanced surface quality, and greater tensile strength due to the work-hardening effect. The cold finishing process also produces a tighter diameter tolerance, making it ideal for applications requiring high accuracy. Because of these characteristics, cold finished steel bars are often preferred in manufacturing components where performance and minor tolerances are critical, such as in assembly or machining tasks requiring exact dimensions. -
Question:
What is ASTM A108, and why is it important?
Answer: ASTM A108 is a standard specification that outlines the requirements for carbon and alloy steel bars that are used in a variety of applications. This standard ensures that materials meet specific mechanical properties and chemical compositions, making it a benchmark for quality and performance in steel products. For businesses and engineers, selecting materials that comply with ASTM A108 allows for a guarantee that the steel pieces are suited for critical applications, helping to prevent failures in service due to material shortcomings. -
Question:
What machining techniques work best for 4140 Alloy Steel?
Answer: Machining 4140 Alloy Steel is best approached with techniques such as turning, milling, and drilling, specifically using high-speed steel or carbide tools. It’s advisable to utilize appropriate cutting fluids to reduce heat and wear during operations. For hardened variants, carbide tools are recommended due to their superior hardness. The bar's annealed form simplifies machining, allowing for smoother cuts and fine finishes, making it suitable for creating detailed components and custom designs in various industries. -
Question:
Where can I buy OnlineMetals 4140 Alloy Steel Round Bar in Palau?
Answer: You can purchase the OnlineMetals 4140 Alloy Steel Round Bar, unpolished mill finish, annealed, and cold finish at Ubuy. Ubuy provides a seamless online shopping experience, offering a range of metal products with reliable quality and service. Whether you're a DIY enthusiast or a professional looking for industrial metals, Ubuy is your go-to platform for acquiring materials like the 4140 steel round bar conveniently.
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USD 303
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Features & Benefits
- Made from durable 4140 Chromoly Steel.
- Provides excellent strength and impact resistance.
- Ideal for high-stress and heavy-duty applications.
- Commonly used in gears, shafts, and fixtures.
- Meets ASTM-A108 standards for quality.
- Perfect for industries requiring reliable performance.
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