Learn about Inconel® 718, a Nickel-Chromium alloy that can be strengthened through precipitation hardening.
Inconel® 718 Overview
This Nickel-Chromium alloy can be strengthened through precipitation hardening and demonstrates excellent creep-rupture strength at elevated temperatures, reaching up to approximately 700°C (1290°F). It surpasses Inconel® X-750 in strength and offers improved mechanical performance at lower temperatures when compared to both Nimonic 90 and Inconel® X-750. In addition, Inconel® 718 is notable for its outstanding weldability, especially when contrasted with other nickel-based superalloys that are hardened using aluminum and titanium.
Inconel® 718 Composition
| C | Mn | Si | P | S | Cr | Ni | Mo | Nb/Cb | Ti | Al | Co | Ta | B | Cu | Pb | Bi | Se | Fe | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Min % | – | – | – | – | – | 17 | 50 | 2.8 | 4.75 | 0.65 | 0.2 | – | – | – | – | – | – | – | Bal |
| Max % | 0.08 | 0.35 | 0.35 | 0.015 | 0.015 | 21 | 55 | 3.3 | 5.5 | 1.15 | 0.8 | 1.0 | 0.05 | 0.006 | 0.3 | .0005 | .0003 | .0003 |
Designations and Specifications
Designations
- W.NR 2.4668
- UNS N07718
Specifications
- AMS 5662
- AMS 5663
- AMS 5832
- AMS 5962
- ASTM B637
- ISO 15156-3
- NACE MR 0175
- API 6A718
Applications
Common Inconel® 718 applications include:
- Turbines
- Aerospace
- Nuclear Reactors
- Automotive
- Oil & Gas Equipment
- Springs
Tensile Strength
| Condition | N/mm² | KSI |
|---|---|---|
| Annealed | <1000 | <145 |
| Condition | As Drawn | After Ageing | ||
|---|---|---|---|---|
| N/mm² | KSI | N/mm² | KSI | |
| No1 Temper & Aged * | 1000 – 1200 | 145 – 175 | 1520 – 1720 | 220 – 250 |
| Condition | As Drawn | After Ageing | ||
|---|---|---|---|---|
| N/mm² | KSI | N/mm² | KSI | |
| Spring Temper & Aged ** | 1250 – 1550 | 180 – 225 | 1700 – 1950 | 247 – 283 |
* No1 or Spring Temper (for ISO 15156-3 / NACE MR 0175) anneal at 1010 °C (1850 °F) for 2 hours and air cool then heat treat at 790 °C (1455 °F) for 6 hours and air cool
** No1 or Spring Temper – Ageing process heat treatment at 718 °C (1330 °F) for 8 hours and adjust temperature to 621 °C (1150 °F) and hold for 18 hours and then air cool
Packaging Options
- Coils
- Spools
- Bars/Cut Lengths
- Custom Packaging Available