Inconel 718 Heat Treatment: AMS 5662/5663 Guide
Date: 2026年8月15日 Categories: News Views: 365
By Shanghai Hangbo Alloy Group Co., Ltd. - China Supplier | ISO 9001:2015 | Est. 2012
Contact: sales@hangboalloy.com | hangbo@nickel-alloy.com | WhatsApp (Lisa): +86 13611656360
Quick Answer: What Is the Correct Inconel 718 Heat Treatment?
Inconel 718 (UNS N07718) requires a two-step precipitation-hardening cycle to reach 1,275+ MPa tensile: Solution anneal at 927-1010C (AMS 5662) or 954-982C (AMS 5663), followed by aging at 718C for 8 hours + 621C for 8 hours total (double age). The critical secret: the 718C/8h step precipitates gamma-double-prime (γ″) while the 621C/8h step precipitates fine gamma-prime (γ′) — together delivering peak strength. This guide covers both AMS conditions, machining, and cost.
The Two AMS Heat Treatment Schedules
| Parameter | AMS 5662 (Annealed) | AMS 5663 (Solution) |
|---|---|---|
| Solution | 927-1010C / 1h / AC | 954-982C / 1h / AC |
| Age Step 1 | 718C / 8h / furnace cool | 718C / 8h / furnace cool |
| Age Step 2 | 621C / 8h / AC | 621C / 8h / AC |
| Tensile | >= 1275 MPa | >= 1275 MPa |
| Yield | >= 1034 MPa | >= 1034 MPa |
| Elongation | >= 12% | >= 12% |
Difference: AMS 5663 specifies a tighter, higher solution temperature for grain-size control in critical rotating components.
Why Double Aging? (The Metallurgy)
Inconel 718 hardens via TWO precipitates:
- γ″ (Ni₃Nb) — precipitated at 718C; the PRIMARY strengthener. Tetragonal, disc-shaped.
- γ′ (Ni₃(Al,Ti)) — precipitated at 621C; secondary fine strengthening.
Aging only at 718C leaves coarse γ″ without the fine γ′ that provides additional strength and creep resistance. The 621C step is the "fine-tune."
Machining Inconel 718: 7 Practical Tips
| Tip | Detail |
|---|---|
| 1. Carbide grades | Use ceramic or coated carbide (CBN for finishing) |
| 2. Speed | 25-40 m/min turning (1/3 of steel speed) |
| 3. Feed | Heavy feed preferred (work-hardens rapidly) |
| 4. Depth | >= 0.5 mm per pass — skip spring passes |
| 5. Coolant | Flooded, high-pressure — never dry |
| 6. Rigidity | Rigid setup mandatory (chatter = work-hardening) |
| 7. Tool angle | Positive rake; hone edges |
Condition & Product Matrix
| Condition | Tensile (MPa) | Typical Use |
|---|---|---|
| Annealed (AMS 5662) | 965-1170 | Machining blanks, non-critical |
| Solution + Aged (AMS 5663) | >= 1275 | Aerospace fasteners, discs |
| Direct-Aged (DA) | >= 1380 | Highest strength, limited ductility |
| Cold-Worked | 1400+ | Springs, retainers |
Price Guide (2026, EXW)
| Form | Price |
|---|---|
| Round Bar Ø50-150 mm | \$28-45/kg |
| Plate 10-50 mm | \$30-48/kg |
| Wire Ø2-5 mm | \$35-55/kg |
Inconel 718 vs A-286 (Quick Comparison)
| Property | 718 | A-286 |
|---|---|---|
| Tensile (aged) | >= 1275 MPa | >= 895 MPa |
| Max Temp | 650C | 700C |
| Cost | 2-3x A-286 | Baseline |
| Weldability | Good (strain-age risk) | Excellent |
Why Buy From Shanghai Hangbo?
- AMS 5662/5663 certified bars, plates, wire in stock.
- EN 10204 3.1 MTC with chemistry + mechanicals per heat.
- Triple aging performed in-house on request.
- SGS/TUV/BV inspection available.
- VIM+ESR melting traceability.
Contact & Complete Product Range
Shanghai Hangbo Alloy Group Co., Ltd. - China Supplier
Email: sales@hangboalloy.com | WhatsApp (Lisa): +86 13611656360 | www.nickel-alloy.com
All Grades
Ni: NI200-N6 | Monel: 400-502, K-500, R-405 | Inconel: 600-740H, X-750, 725 | Incoloy: 800-27-7MO | Hastelloy: C-276-HYBRID-BC1, N | Super Austenitic: 904L-AL-6XN | Chromium-Rich: Alloy 33 | High-Strength Stainless: Nitronic 50/60, PH13-8Mo | Chlorination: Alloy 45 | Nimonic: 75-263 | Haynes: 25-HR-160 | RA: 330/333 | Precision: 1J22-4J45 | High-Strength: 18Ni250-AerMet100 | Heating: Cr20Ni80/60 | Specialty: Alloy 20-602CA
Related Products & Where to Buy
For AMS-certified Inconel 718 (UNS N07718) round bars and forgings or Inconel 625 (UNS N06625) round bars and seamless tubes, visit the product pages or contact Shanghai Hangbo Alloy Group.
Product Forms: Bars(6-500mm) | Tubes(OD 6-610mm) | Plates(0.1-100mm) | Forgings | Welded Pipes | Fittings | Wire(0.05-10mm) | Strip(0.02-4.0mm)
SGS/BV/TUV. www.nickel-alloy.com
