4340 Steel CNC Machining In China

At our company, we specialize in providing 4340 steel CNC machining services to clients who require precision parts made from this material. 4340 alloy steel is a high-strength and durable material that is common in the manufacturing of aircraft parts, automotive components, and other heavy-duty applications. It is known for its toughness, resistance to wear and tear, and ability to withstand high-stress levels.

We produce complex shapes and designs with unparalleled accuracy. Whether you need a small batch of parts or a large-scale production run, we can deliver high-quality results that meet your exact specifications. Trust us for all your 4340 steel CNC machining needs, and experience the benefits of working with an industry leader in precision engineering.

Our CNC Machining Capabilities for 4340 Steel Machined Parts

Our CNC machining capabilities for 4340 alloy steel include turning, milling, 5-axis machining, and surface finishing. We can manufacture parts with complex shapes and sizes and produce parts in large quantities with repeatable precision.

5 axis CNC machining

Turning – We use CNC lathes to produce precision turning parts for alloy steel 4340.

Milling – Our mills are designed to produce highly accurate 4340 steel parts with tight tolerances.

5-axis machining – Our 5-axis machines can create highly complex parts with unparalleled accuracy.

Surface finishing – We offer various surface finishing options, including grinding, polishing, and tumbling, to meet our customers’ needs.

Surface finishing for 4340 steel parts

Surface finishing is an important aspect of machining 4340 steel parts as it can improve their durability, corrosion resistance, appearance, and overall performance. Here are some common surface finishing techniques that can be applied to 4340 steel parts:

This technique uses abrasive wheels to remove surface imperfections, creating a smooth surface finish.

Plating involves depositing a thin metal layer, such as nickel or chromium, onto the part’s surface to improve its corrosion resistance and aesthetics.

Polishing uses abrasives and compound agents to create a shiny, smooth surface on the part.

Coatings such as paint or powder coating can be applied to the part’s surface to provide enhanced durability and resistance to environmental factors.

Common Applications for 4340 Steel machined parts

4340 steel machined parts have numerous applications in various industries. Some of the most common applications include:

Aerospace industry – 4340 steel machined parts are used in aircraft engines, landing gear, and other critical components.

Automotive industry – This material is used to manufacture parts for high-performance automobiles, such as crankshafts, connecting rods, and gears.

Oil and gas industry – 4340 steel is used to manufacture oil and gas drilling equipment, such as drill bits, mud motors, and stabilizers.

Tool and die industry – This material manufactures high-performance cutting tools, molds, and dies.

4340 alloy steel parts
4340 steel parts
alloy steel 4340 machined parts

Why Choose Our Alloy Steel 4340 Machining Services China?

High-Quality Machining

Our machining services are done by skilled professionals with years of experience, ensuring that your components are made to the highest standard.

Competitive Pricing

We offer competitive pricing for all of our machining services, ensuring you get the best possible value for your money.


We offer various machining services, including CNC, milling, turning, and more. This allows us to cater to various industries and requirements, ensuring we can meet your needs.

Fast Turnaround Times

We understand that time is of the essence when it comes to machining components. That's why we offer fast turnaround times, so you can get your components as soon as possible.

Other materials for CNC machining

4340 Alloy Steel Machining FAQs

4340 steel is a nickel-chromium-molybdenum alloy steel that exhibits good machining properties. Some of the key machining properties of 4340 steel include:

Machinability: 4340 steel has good machinability in the annealed or normalized condition.

Hardness: When heat treated, 4340 steel exhibits high hardness and can be difficult to machine.

Tensile Strength: 4340 steel has a high tensile strength of at least 150 KSI, making it suitable for high-stress applications.

Toughness: The toughness of 4340 steel is high, making it resistant to cracking or breaking under high forces.

Welding: Welding 4340 steel can be challenging because it can lead to hard, brittle areas in the heat-affected zone. However, proper welding techniques can minimize these issues such as preheating and post-weld heat treatment.

Surface Finish: 4340 steel can be ground, machined, or polished to a high surface finish.

Wear resistance: 4340 steel exhibits excellent wear resistance, making it ideal for parts that experience high wear.

Heat Resistance: 4340 steel has good heat resistance, making it ideal for high-temperature applications such as turbine components.

Overall, 4340 steel is a versatile alloy with good machinability properties, making it ideal for various high-stress applications.

4340 steel can be challenging to machine due to its high strength, toughness, and abrasiveness. Its hardness can vary depending on the heat treatment, affecting its machinability.

Machining 4340 steel requires proper tool selection, cutting speeds and feeds, and lubrication to prevent tool wear and workpiece deformation.

However, with proper machining techniques and the right equipment, 4340 steel can be successfully machined to produce high-quality components.

The advantages of 4340 steel CNC machining include the following:

a. Precision – Our CNC machines can achieve high precision and accuracy, which is essential for many industries.

b. Complex shapes – With our CNC machines, we can manufacture parts with intricate and complex shapes.

c. Repeatable production – Our CNC machines can produce parts with repeatable precision, making it ideal for mass production.

d. Efficiency in manufacturing – CNC machining is a highly efficient manufacturing process, reducing waste and errors in the production process.

Quality control is our top priority, and we have strict procedures and standards to ensure that our products are of the highest quality.

And we use highly precise CNC machines, inspect finished products thoroughly, and follow strict quality control procedures to ensure the accuracy of our machining.

Tips for Successful 4340 Steel CNC Machining

To achieve successful 4340 steel CNC machining, there are several tips to consider:

a. Appropriate cutting tools and parameters – The right cutting tools and parameters are essential for high-quality machining.

b. Adequate cooling and lubrication – Coolant and lubrication can reduce heat buildup and prolong tool life.

c. Minimizing chatter and vibration – Chatter and vibration can lead to errors and reduced precision, so minimizing them is important.

d. Proper fixture design – A well-designed fixture can reduce deflection and improve accuracy.

What is the difference between 4130 and 4340 alloy steel?

The main difference between 4130 and 4340 alloy steel is their chemical composition and properties.

4130 steel contains a lower percentage of carbon, making it easier to weld and form. It also has good strength, toughness, and ductility, making it suitable for aircraft parts and structural tubing applications.

In contrast, 4340 steel contains more carbon, nickel, and chromium, giving it high strength, toughness, and wear resistance. It is commonly used in applications that require high strength and durability, such as aircraft landing gear, crankshafts, and transmission gears.

Despite these differences, 4130 and 4340 steel are commonly used in the aerospace and automotive industries due to their excellent mechanical properties.

Looking for a China Manufacturer of custom 4340 steel parts?

We are a China manufacturer of custom CNC parts. Our CNC machining services for 4340 steel offer a reliable and efficient solution for businesses looking for high-quality, precision parts that meet or exceed customer specifications. We provide customization and flexibility, competitive pricing, and fast turnaround times. For more information or to customize CNC parts, contact us today.