- Home Page /
- Industrial Supplies /
- Raw Materials /
- Metals & Alloys /
- Steel /
- Rods /
- 4140 Alloy Steel Round Bar, Unpolished Mill F...
0 ratings
Item #:
143863613
4140 Alloy Steel Round Bar, Unpolished Mill Finish, Annealed, Cold Finish, ASTM A108, 0.75 Diameter, 72 Length, OnlineMetals
Item #:
143863613
€ 91
Price Details
Excluding Shipping & Custom charges ( Shipping and custom charges will be calculated on checkout )
*All items will import from US
0 ratings
Write a review
In stock
Imported from USA store
QTY:
Order now and get it around Sunday, August 23
Secured transaction
Ubuy works hard to protect your security and privacy. Our advanced payment security system ensures confidentiality by encrypting your information during transmission using AES (Advanced Encryption Standards) and SSL (Secure Socket Layer) protocols. Your payment details are 100% secure as we do not share your payment details with third party sellers.
Our Top Logistics Partners
4140 alloy steel is known for strength, resistance to fracturing, abrasion, and impact in high stress applications.
Fast
Shipping
Free
Return*
Secure Packaging
100% Original Products
PCI DSS Compliance
ISO 27001 Certified
Note: Step Down Voltage Transformer required for using electronics products of US store (110-120). Recommended power converters Buy Now.
What Stands Out
High Strength
4140 alloy steel offers exceptional strength and hardness, making it ideal for demanding applications like machinery and tooling, ensuring durability under pressure.
Versatile Applications
Perfect for fabrication, machining, and construction, this round bar is suitable for a wide range of industrial uses, ensuring adaptability across multiple projects.
Precision Finish
Cold finished for tight tolerances, this unpolished round bar maintains dimensional accuracy, enhancing performance in precise engineering applications, leading to improved project outcomes.
Product Details
| Item Diameter | 0.75 Inches (1.9 cm) |
| Item Thickness | 0.75 Inches (1.9 cm) |
| 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 | 120605 |
| Part Number | 15488 |
| Unit Count | 6.0 Feet |
| Manufacturer | OnlineMetals |
| Brand | Online Metals |
| Shape | Round |
| Item Weight | 11.5 lbs (5.22 kg) |
Who Should Buy?
-
Mechanical Engineers
Ideal for engineers needing durable materials for designing machinery and structures requiring high tensile strength.
-
Metal Fabricators
Perfect for fabricators who require precision cutting and shaping of alloy steel for industrial applications.
-
DIY Enthusiasts
Great choice for hobbyists looking to create custom metal projects that need solid and reliable material.
-
Non-Metal Workers
Not suitable for users without metalworking skills, as handling requires specific tools and techniques.
Product Description
4140 Alloy Steel Round Bar, Unpolished Mill Finish, Annealed, Cold Finish, ASTM A108, 0.75 Diameter, 72 Length, OnlineMetals
Have any Query? Chat with us
Customer Questions & Answers
-
Question:
What are the main characteristics of 4140 alloy steel?
Answer: 4140 alloy steel is known for its high strength, toughness, and good fatigue resistance. It is a chromium-molybdenum steel that is ideal for applications requiring moderate to high strength and excellent wear resistance. The annealed state ensures that the steel is easy to machine while still retaining its strength properties once hardened, making it suitable for components like gears, axles, and shafts. -
Question:
What is the typical use of a 0.75" diameter 4140 round bar?
Answer: A 0.75" diameter 4140 round bar is often used in the manufacture of various components such as structural parts, fasteners, and automotive applications. Its mechanical properties make it suitable for parts that require strength and durability under heavy loads, like drill bits and valve components. Additionally, its cold finish provides improved dimensional accuracy, making it an excellent choice for precise engineering applications. -
Question:
Is the unpolished (mill) finish suitable for my application?
Answer: Yes, an unpolished (mill) finish offers a rough surface texture that can be ideal for applications where surface finish is not critical. This finish can be beneficial for maintaining strong bonding with adhesives or coatings. Moreover, for machined applications, it allows for easier surface modification, making it a popular choice among fabricators and engineers. -
Question:
Can the 4140 round bar be heat-treated?
Answer: Absolutely, 4140 alloy steel can be heat-treated to enhance its hardness and strength. Depending on the desired mechanical properties, it can be quenched and tempered to achieve different levels of hardness. This adjustability allows users to customize the steel's characteristics to meet specific performance requirements in high-stress applications. -
Question:
What are the differences between annealed and cold-finished 4140 round bars?
Answer: Annealed 4140 round bars are softened through a heat treatment process, making them easier to work with and machine. Cold-finished 4140, on the other hand, undergoes additional processing after initial shaping, resulting in improved surface finish and tighter tolerances. This makes cold-finished bars a better choice for precision applications, whereas annealed bars are excellent for forming and shaping operations. -
Question:
How do I know if 4140 alloy steel is the right choice for my project?
Answer: Choosing 4140 alloy steel depends on your project's requirements. If you need high strength, wear resistance, and toughness in extreme conditions, 4140 is an optimal choice. Evaluating factors like operating temperature, load conditions, and environmental exposure can help you determine its suitability. For applications such as heavy machinery, automotive parts, or tooling, 4140 often meets the necessary performance standards. -
Question:
What is ASTM A108, and why is it important for 4140 steel?
Answer: ASTM A108 is a standard specification for steel bars that undergo a cold finishing process. It guarantees certain mechanical properties and specifies allowable manufacturing variations. Compliance with ASTM A108 ensures that the 4140 steel meets industry standards for quality and performance, making it essential in sectors where precision and reliability are paramount. -
Question:
What factors affect the machinability of 4140 alloy steel?
Answer: The machinability of 4140 alloy steel is influenced by its hardness, microstructure, and the condition of the material. In its annealed state, 4140 is relatively easy to machine. However, if it has been hardened, specialized machining techniques or tools may be required. Understanding the specific alloy and finshing process can help optimize machining operations for efficiency and effectiveness. -
Question:
How do I properly store 4140 alloy steel round bars?
Answer: To ensure the longevity of 4140 alloy steel round bars, they should be stored in a dry, indoor environment to prevent rusting and corrosion. Using protective coverings can provide additional protection against moisture. Additionally, keeping the bars off the ground and secured properly can help avoid physical damage or deformation. -
Question:
Where can I buy 4140 Alloy Steel Round Bar, Unpolished (Mill) Finish, Annealed, Cold Finish, ASTM A108, 0.75" Diameter, 72" Length in Malta?
Answer: You can purchase 4140 Alloy Steel Round Bar from Ubuy in Malta. Ubuy offers a convenient online shopping experience, featuring a variety of metals and materials including this specific 4140 round bar. Their extensive catalog and user-friendly interface make it easy to find the products you need for your projects.
OnlineMetals Rods 120605 Editorial Review
The 4140 Alloy Steel Round Bar has received a generally positive reception from customers, who praise its quality and versatility for a range of applications. Users highlighted the robustness of the rod, noting its effectiveness in crafting tools and supports, with particular emphasis on its suitability for projects involving both structural stability and detailed work, such as making dress form stands. Many customers appreciated the accuracy of the dimensions, with the rod typically meeting or coming close to the specified measurements. The mill finish of the steel seems to appeal to those who value a raw bar that can be worked on, with tools machining well without major issues. However, some concerns were raised regarding minor defects; a few users noted that the bar had slight bends which affected its performance on a lathe. While most reviews speak highly of the product, there were isolated complaints about discrepancies between the advertised specifications and the actual product received, particularly regarding coating and diameter mismatches. Overall, the 4140 Alloy Steel Round Bar stands out as a dependable option for DIY enthusiasts and professional machinists alike, offering quality metal ready for various projects. ###
Customer Reviews & Ratings
1 customers ratings
-
5 Star
0%
-
4 Star
100%
-
3 Star
0%
-
2 Star
0%
-
1 Star
0%
Review this product
Share your thoughts with other customers
Pros
- High-quality alloy steel
- Versatile for multiple applications (tools, supports, etc.)
- Good dimensional accuracy
- Machinable with standard tools ###
Cons
- Some users reported slight bends affecting performance
Platform Trust & Buyer Confidence
MA
Mohammad
Verified buyer
“Excellent quality and original too,when ubuy send original things I will appreciate that ,I very satisfied thank you”
23 July 2026 · via Trustpilot
CK
Chitra
Verified buyer
“The order and delivery progress was communicated very well. Package arrived within the estimated time. Products arrived as expected in good condition.”
22-Jul-26 · via Trustpilot
K
kund
Verified buyer
“Good supply of products. Safe payment methods, and shipment worldwide! Genuine products.”
23-Jul-26 · via Trustpilot
OO
Onesi
Verified buyer
“Was my first time buying a product from Ubuy, but I found it so helpful. This is reliable. Gonna place a new order!”
22 July 2026 · via Trustpilot
SJ
SAO JOHN
Verified buyer
“Ubuy is a great online platform to buy stuff. Reliable, fast delivery time and great value for money. I've been using Ubuy online shopping platform for three years now and will continue to do so.”
23 July 2026 · via Trustpilot
Secure Checkout
Global Delivery
Easy Returns
Genuine Products
Product Price History
Important information
- Limitations : For products shipped internationally, please note that any manufacturer warranty may not be valid; manufacturer service options may not be available; product manuals, instructions, and safety warnings may not be in destination country languages; the products (and accompanying materials) may not be designed in accordance with destination country standards, specifications, and labeling requirements; and the products may not conform to destination country voltage and other electrical standards (requiring use of an adapter or converter if appropriate). The recipient is responsible for assuring that the product can be lawfully imported to the destination country. When ordering from Ubuy or its affiliates, the recipient is the importer of record and must comply with all laws and regulations of the destination country.
- Not all the products listed on Ubuy are for sale, as Ubuy is a global search engine. Products are subject to export/trade regulations.
€ 91
Order now and get it around Sunday, August 23
This item is not restrict in my country.(Please click on above link if this item is not restrict in your country, So our team will review and allow.)
QTY:
Secured transaction
PCI DSS compliant and ISO 27001:2022 certified, with encrypted payments and full buyer protection on every order.
Our Top Logistics Partners
Fastest cross-border delivery
Features & Benefits
- Made from high-strength 4140 alloy steel for durability.
- Cold finished and annealed for optimal formability and toughness.
- Meets stringent ASTM A108 specifications for quality assurance.
- Can be heat treated for increased hardness, enhancing its applications.
- Ideal for demanding use in gears, shafts, spindles, and more.
- High resistance to wear and impact, making it perfect for heavy-duty applications.
Ubuy Assurance
Experience worry-free shopping with 100% original products, PCI DSS-compliant payment security, ISO 27001-certified data protection, the fastest cross-border delivery, free returns *, and secure packaging on every order.