When sourcing high-performance alloys for extreme environments, Nimonic 90 and Inconel 718 are often considered. Both of these nickel-based superalloys are used in high-temperature applications such as aerospace, gas turbines, and industrial gas compressors. However, they are optimized for different performance characteristics and application scenarios. Understanding their key differences in composition, mechanical properties, and applications is crucial for making the right procurement decision.
What is NIMONIC® alloy 90?
NIMONIC® alloy 90 (UNS N07090/W. Nr. 2.4632) is a wrought nickel-chromium-cobalt base alloy strengthened by additions of titanium and aluminum. It has been developed as an age-hardenable creep- resisting alloy for service at temperatures up to 920°C (1688°F.It can be processed into various practical product forms, including sheets, coils, tubes, rods, and wires.
Is Inconel 718 hard to machine?
This nickel-based superalloy, a staple in aerospace applications, offers excellent strength and heat resistance-but those same properties make it notoriously difficult to machine. Inconel 718 tends to work-harden quickly, generating extreme heat at the tool–workpiece interface, and accelerating tool wear.
Nimonic 90 vs. Inconel 718: Key Differences
| Alloy | Key Characteristics | Primary Applications |
|---|---|---|
| Nimonic 90 | Precipitation-hardened, high-temperature strength | Gas turbines, jet engine components, power plant turbines |
| Inconel 718 | Precipitation-hardened, excellent creep and fatigue resistance | Aerospace engine parts, pressure vessels, high-temperature fasteners |
Nimonic 90 offers exceptional creep strength at temperatures above 650°C, ideal for high-stress turbine applications.
Inconel 718, with excellent high-temperature tensile strength, is suited for critical rotating components in aerospace and power generation.
Chemical Composition Comparison (wt. %)
| Element | Nimonic 90 (UNS N06090) | Inconel 718 (UNS N07718) | Procurement Impact |
|---|---|---|---|
| Nickel (Ni) | Balance (~60%) | 50–55% | Core alloy for corrosion & temperature resistance |
| Chromium (Cr) | 18–20% | 17–21% | Enhances oxidation resistance |
| Molybdenum (Mo) | 3.0–3.5% | 2.8–3.3% | Corrosion resistance in acidic environments |
| Iron (Fe) | ≤ 5% | Balance (Fe) | Balance element for cost efficiency |
| Titanium (Ti) | 2.5–3.0% | 0.65–1.15% | Precipitation hardening |
| Aluminum (Al) | 1.0–1.5% | 0.2–0.8% | Strength enhancement via γ′ and γ″ phases |
| Cobalt (Co) | 8–10% | ≤ 1.0% | Impact on strength at high temperature |
| Niobium (Nb) | 2.5–3.0% | 4.75–5.5% | Strengthening phase in Inconel 718 |
Mechanical Properties Comparison (Room Temperature)
| Property | Nimonic 90 | Inconel 718 |
|---|---|---|
| Tensile Strength | 1,400–1,600 MPa | 1,240–1,450 MPa |
| Yield Strength | 1,100–1,300 MPa | 1,030–1,200 MPa |
| Elongation | 10–20% | 12–20% |
| Hardness (HRC) | 40–45 HRC | 36–45 HRC |
| Density | 8.18 g/cm³ | 8.19 g/cm³ |
High-Temperature Mechanical Performance
| Temperature (°C) | Nimonic 90 | Inconel 718 |
|---|---|---|
| 650 °C | 1,000 MPa | 720 MPa |
| 700 °C | 950 MPa | 650 MPa |
| 800 °C | 800 MPa | 500 MPa |
| 900 °C | 600 MPa | 400 MPa |
Creep and Fatigue Resistance
| Alloy | Creep Strength (at 700°C) | Fatigue Strength |
|---|---|---|
| Nimonic 90 | Very high | High |
| Inconel 718 | High | Very high |
Inconel 718 suppliers
At GNEE, Inconel 718 is available in various forms to meet diverse industrial needs:
Plates and Sheets (cold rolled and hot rolled)
Bars and Rods (round, square, hexagonal)
Tubes (seamless and welded)
Wires and Strips (for springs, fasteners, electrical applications)
Forgings and Custom Parts (according to drawings or specifications)
Specifications: UNS NO7718, WNR 2.4668, AFNOR NC19FeNb, JIS NCF 718, GOST ХН75МБТЮ, EURONORM NiCr22Mo9Nb, OR ЭИ602, BS NA 21.
Temperature Range: -423°F to 1300°F.
Testing and Documentation: Mill Test Certificates, EN 10204 3.1, Chemical Reports, Mechanical Reports, Destructive Testing Reports, Non-Destructive Testing Reports, PMI Test Reports, Visual Inspection Reports, Third-Party Inspection Reports, NABL Certified Laboratory Reports.
Packaging: Wooden crates, bubble wrap, steel strapping, or packaged according to customer requirements.
