The Ultimate Guide to Machining Inconel 718: Challenges, Techniques, and Expert Insights

As a material widely used in aerospace, energy, and high-performance engineering, Inconel 718 presents both tremendous value and serious manufacturing challenges. At MyT Machining, we have developed advanced strategies to deliver precision components using this tough material. In this article, we explore every essential aspect of machining Inconel 718—from its metallurgy and mechanical behavior to optimized cutting techniques, tooling, and industry use cases.

Whether you’re a product designer, manufacturing engineer, or procurement specialist, this guide offers actionable insights into how to work with Inconel 718 for high-stakes applications.

What Is Inconel 718?

Inconel 718 is a precipitation-hardenable, nickel-chromium alloy designed for high-strength performance in extreme environments. It’s known for:

• Excellent tensile and fatigue strength

• High-temperature performance (up to 1300°F / 700°C)

• Corrosion and oxidation resistance

• Outstanding weldability

The alloy is composed primarily of nickel, with significant levels of chromium, iron, niobium, and molybdenum, which make it suitable for aggressive environments like jet engines, downhole oil tools, and turbine systems.

Why Inconel 718 Is So Difficult to Machine

While Inconel 718 excels in strength and resistance properties, these characteristics also make it a difficult material to cut using traditional methods. Here are the top machining challenges:

1. Work Hardening

When cutting forces are applied, Inconel 718 hardens rapidly, making subsequent machining passes more difficult and abrasive.

2. Low Thermal Conductivity

Heat generated during cutting stays near the tool tip, increasing tool wear and affecting surface integrity.

3. High Strength and Toughness

The material resists deformation and cutting, which requires robust tooling and high machine rigidity.

4. Tool Wear

Even high-quality carbide tools tend to wear quickly unless used under optimal conditions with the right coatings and coolants.

Best Practices for Machining Inconel 718

At MyT Machining, our approach to Inconel 718 involves tailored tool paths, cutting parameters, and machine strategies. Here's what we recommend:

1. Choose the Right Cutting Tools

• Use high-performance carbide inserts with TiAlN or AlTiN coatings.

• For finishing operations, ceramic inserts may be more effective due to their heat resistance.

2. Optimize Speeds and Feeds

• Cutting speeds: 20–40 m/min

• Feed rates: Consistent and moderate to avoid chatter and overhardening

• Depth of cut: Avoid shallow cuts; they tend to rub instead of shear

3. Use High-Pressure Coolant

Coolant at 1000 psi or more helps reduce heat buildup, flush chips, and extend tool life.

4. Maintain Rigidity

Machine vibration must be minimized. Use short tool overhangs and rigid workholding fixtures to ensure stability.

5. Apply Toolpath Strategies

Trochoidal milling and adaptive roughing strategies reduce cutting pressure and heat while maintaining high material removal rates.

MyT Machining’s Expertise with Inconel 718

MyT Machining specializes in high-difficulty materials, and Inconel 718 is a core part of our capability set. Here’s why customers across industries trust us with their most demanding parts:

Advanced CNC Equipment

We utilize multi-axis CNC lathes and mills with live tooling, in-process monitoring, and thermal compensation to ensure reliable, high-tolerance results.

Custom Tooling Strategies

Our machinists work closely with our engineers to define the best combination of cutting inserts, tool coatings, and feed strategies for each job.

Quality Assurance

We use CMM (Coordinate Measuring Machine) inspections and high-precision gauges to verify dimensions and surface integrity at every stage of production.

Flexible Volume Support

From prototypes to high-volume production, we scale our processes to match your schedule and technical requirements.

Typical Inconel 718 Applications

Inconel 718’s strength and durability make it ideal for high-stress and high-temperature environments. Examples include:

• Aerospace: Turbine disks, compressor blades, exhaust systems, brackets

• Oil & Gas: Downhole tools, valves, pump components

• Power Generation: Heat exchangers, nuclear reactor components

• Medical: Surgical tools and devices requiring high corrosion resistance

• Automotive (Motorsports): Turbochargers, high-performance engine parts

Every application demands tight tolerances and rigorous inspection—which we deliver consistently.

Design Considerations for Machining Inconel 718

If you’re engineering a part to be machined in Inconel 718, keep the following tips in mind:

• Avoid unnecessary tight tolerances: Only use where essential to reduce machining cost and time.

• Keep wall thickness consistent: Uneven walls can lead to warping due to localized heating.

• Simplify geometries: Reduces cycle time and tool wear.

• Avoid deep slots or holes without access for chip evacuation or coolant.

Need help optimizing your design? MyT Machining offers DFM (Design for Manufacturability) consultations at no extra charge.

The Future of Machining Superalloys

Technological advances are making Inconel 718 machining more feasible and efficient:

• AI-Based Toolpath Optimization: Adapts feed and speed rates dynamically.

• Hybrid Machining Systems: Combine additive and subtractive techniques.

• Advanced Tool Materials: New carbide grades and ceramic composites with better resistance to abrasion.

• Digital Twins & Simulation: Simulate tool wear and heat zones before actual machining begins.

MyT Machining stays ahead of the curve by investing in research and equipment upgrades that directly benefit our clients.

Why Choose MyT Machining?

Choosing a CNC shop for machining Inconel 718 isn’t just about who owns a machine—it’s about who understands the behavior of this material and how to achieve repeatable results. MyT Machining brings:

• Decades of experience in superalloy machining

• State-of-the-art equipment

• Tight process control

• On-time delivery, every time

We’re not just a service provider—we’re a long-term manufacturing partner for high-spec industries.

Conclusion

Machining Inconel 718 is complex, but when done properly, it enables the production of high-performance parts that survive the world’s most demanding environments. Whether you're designing aerospace components, oilfield tools, or power generation parts, MyT Machining offers the expertise, technology, and precision you need.

Partner with us to turn your most challenging designs into reality—with consistency, speed, and quality assurance that sets us apart.