Stop wasting your expensive CNC tools! While many nickel alloys are notoriously difficult to machine, Nimonic 75 (NiCr20Ti) is a highly forgiving superalloy when you have the right machining data. As a professional nickel alloy manufacturer, Gnee Steel not only provides high-quality materials but also the machining data sheets you need for efficient production. Our mirror-polished H9 precision-ground bars can be directly fed into automatic lathes, significantly reducing machining cycles and overall procurement costs.
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Nimonic 75 (NiCr20Ti) Machining Data Sheet
Nimonic 75 (NiCr20Ti) Machining Data Sheet
Nimonic 75 is a nickel-chromium-based solid solution strengthened superalloy, renowned for its high-temperature strength and excellent corrosion resistance. Its machinability is approximately 17%, and its hardness is approximately 90 HRB, thus it is considered a difficult-to-machine alloy, requiring specialized tools and machining parameters. However, it is also one of the more machinable materials in the nickel-based heat-resistant superalloy (HRSA) family.
How machinable is NIMONIC 75?
Nimonic 75 is a nickel-based heat-resistant superalloy (HRSA) material with a machinability grade of 17% and a hardness of 90 HRB.
1. Equivalent International Designations for Material Nimonic 75
| Standard | Name |
|---|---|
| wnr | 2.4630 |
| din | NiCr20Ti |
| uns | UNS N06075 |
| bs | HR5, 203.4 |
| anfor | NC20T |
2. Chemical Composition for Material Nimonic 75
| Element | Amount |
|---|---|
| Nickel (Ni) | 76% |
| Chromium (Cr) | 20% |
| Iron (Fe) | 4% |
| Silicon (Si) | 0.45% |
| Manganese (Mn) | 0.45% |
| Carbon (C) | 0.45% |
| Titanium (Ti) | 0.35% |
| Aluminum (Al) | 0.1% |
Click to download the GH3030 alloy PDF file now
3. Nimonic 75 Material Cutting Speed Recommendations
* Check the speeds below for higher accuracy under specific conditions!
| Application | Vc (m/min) | Vc (SFM) |
|---|---|---|
| Turning | 60-80 | 200-260 |
| Milling | 45-60 | 150-200 |
| Parting | 35-50 | 110-160 |
| Grooving | 50-70 | 160-230 |
| Drilling | 45-60 | 150-200 |
4. Nimonic 75 Machining Principles
Cutting Tools: Use carbide tools with sharp cutting edges to avoid work hardening. PVD-coated tools are recommended for both turning and milling.
Coolant: A large amount of coolant is crucial for reducing heat, which is a major challenge in machining this alloy.
Condition: Machining is best performed in the annealed condition.
Nimonic 75 Turning Parameters
Cutting Speed (Vc): Roughing approx. 30-60 m/min, Finishing approx. 50-80 m/min.
Feed Rate (f): 0.1-0.3 mm/revolution, adjusted according to depth of cut.
Depth of Cut (ap): 0.5-3 mm, focusing on avoiding cutting into previously work-hardened surface layers.
Nimonic 75 Milling Parameters
Cutting Speed (Vc): Typically 25-50 m/min.
Feed Rate (fz): 0.05-0.15 mm/tooth.
Tools: Use end mills with high positive geometry to improve cutting performance.
Drilling and Other Machining
Drilling: Use high-rigidity short-flute drills and high-pressure coolant.
Work Hardening: Due to the rapid work hardening rate of the Nimonic 75, it is essential to avoid tool dwell or friction on the surface, as this can lead to surface hardening and premature tool failure.
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5. Gnee Steel Solves Your Problems: Tool Life and Precision
A Concern in CNC Shops: "Nickel alloys often undergo instantaneous work hardening, leading to breakage of small drills and boring bars."
Our Nimonic 75 Solution from Gnee Steel:
VIM + ESR Purity: Our bars are free of hard non-metallic inclusions that can cause carbide tools to "die suddenly."
h9 Precision Grinding: Consistent diameter (micron-level) ensures your automatic feeders won't jam and your chucks always maintain perfect clamping force.
Ra ≤ 0.8μm Surface Finish: Mirror polishing eliminates the need for post-machining secondary polishing, thus improving your return on investment (ROI).
Contact us now to get the latest export price for GH3030 in 2026
FAQ
Q1: What are the recommended cutting speeds (V) for Nimonic 75?
A: For rough turning with carbide tools, we generally recommend 25-40m/min. For finishing, this can be increased to 40-60m/min. Our fulMachining Datasheet provides specific feeds for drilling, threading, and milling.
Q2: Should I use water-based or oil-based coolant?
A: High- pressure water-based coolant (8-10% concentration) is excellent for heat removal. However, for tapping and heayy-duty slow-speedoperations, sulfur-free chlorinated oils provide better lubrication to prevent galling.
Q3: Is Nimonic 75 (GH3030) easier to machine than Nimonic 80A?
A: Significanty. Nimonic 75 does not have the hard precipitates that Nimonic 80A nas. You can expect up to 50% longer toolife when switchingto Nimonic 75 for parts that only require oxidation resistance without extreme mechanical loads.