AMS 5663 Material: Properties, Hardness, Density, Specification

AMS 5663 identifies precipitation-hardened bar and forgings of Alloy 718 (Inconel® 718, UNS N07718) supplied in the aged condition; it is a high-strength, nickel-chromium-niobium alloy whose minimum room-temperature performance in the AMS 5663 condition typically includes ≥185 ksi ultimate tensile strength, ≥150 ksi yield, ≥331 HB hardness and ~8.19 g/cm³ density — making it a first-choice material where sustained strength, toughness and resistance to corrosive or high-temperature environments are required (aerospace, turbomachinery, oil & gas).

What is AMS 5663 covers

AMS 5663 is an SAE/AMS material specification that covers precipitation-hardened bar and forgings of Alloy 718 supplied in an aged (solution + age hardened) condition intended for high-strength, corrosion and heat-resistant applications. The spec defines required melting practice, chemical limits, mechanical property minima, heat-treatment practice and acceptance tests for bar/forgings within the size limits stated in the standard. Its purpose is to ensure repeatable, mill-certified performance for demanding aerospace and industrial uses.

Where AMS 5663 fits in the Alloy 718 family and equivalents

“Alloy 718” is a widely used nickel-chromium alloy with niobium (columbium), titanium and aluminum additions that impart precipitation hardening (γ″ and γ′ phases). Equivalent identifiers and cross-references commonly used in procurement and material data are:

• UNS N07718 — universal UNS designation for Alloy 718.

• AMS 5662 / AMS 5663 / AMS 5664 — related AMS specs that cover different product forms and heat-treatment conditions (AMS 5662 often covers solution-treated bar/forgings; AMS 5663 applies to aged/precipitation-hardened bar/forgings).

When buyers request “Inconel 718 AMS 5663” they are specifying the aged bar/forging condition that arrives to the shop already precipitation-hardened; this affects machinability and final part processing (aged material is stronger but more difficult to cut).

Chemical composition - standard limits and practical notes

Below is a condensed specification-style table of the principal elements and common limits for Alloy 718 (values shown are typical AMS limits ranges used in industry documents — always confirm with the mill certificate / AMS text for acceptance limits):

Note: AMS specifications include tight limits for tramp elements and require specific melting methods (for high-quality mill stock, VIM/VAR or equivalent multiple melting practice) to control segregation and inclusions. The Nb/Ta content and the Ti/Al balance are central to the alloy’s age-hardening response.

(For authoritative chemical tables and official element limits consult the AMS 5663 document and product datasheets from producers.)

Mechanical properties and hardness (typical minima in AMS 5663 condition)

Manufacturers and specification summaries for AMS 5663 commonly list the following minimum properties for aged bar/forgings supplied under AMS 5663:

Because AMS 5663 requires supply in the precipitation-hardened condition, these elevated strengths and hardness numbers are expected out of the box. When parts are required to be machined extensively, some shops prefer AMS 5662 (solution annealed) and then perform final aging after machining to minimize tool wear; AMS 5663 avoids post-machining heat treat when a hardened finished part is required.

Physical properties - density, melting and thermal behavior

Alloy 718 is a dense nickel-base alloy with the following commonly reported physical values:

• Density: ~8.19 g/cm³ (0.296 lb/in³).

• Melting / melting range: ~1260–1336 °C (approx. 2300–2437 °F), depending on composition and measurement method.

• Thermal conductivity: relatively low compared with steels; typical values around 10–12 W/m·K near room temperature (varies with condition).

These values matter for stiffness, thermal mass, heat-treat planning, and machining thermal management.

Heat treatment and metallurgical condition

AMS 5663 parts are solution treated then aged to form a dispersion of γ″ and γ′ precipitates that drastically increases strength:

• Solution treatment: high-temperature hold to dissolve solute clusters (typical solution anneal ~980–1060 °C depending on product form).

• Aging: controlled two-step aging schedule (commonly ~720 °C for several hours followed by ~620 °C) produces the strengthening precipitates.

Because AMS 5663 material is supplied already aged, mills performing AMS 5663 processing must document their heat treat schedule and provide MTRs (mill test reports) confirming hardness and tensile testing. The aging cycle and cooling rates directly influence toughness, creep resistance and susceptibility to grain boundary phases — so verify mill process notes if your application has extremes of temperature or cyclic loading.

Fabrication notes: machining, welding and forming

Practical shop considerations for AMS 5663 (aged Alloy 718):

• Machining: aged AMS 5663 is significantly harder and less ductile than solution-annealed material. Expect shorter tool life and slower feeds; many fabricators prefer to machine in the annealed state (AMS 5662 or annealed AMS 5664) and perform aging after finish-machining when geometries and tolerances allow.

• Welding: Alloy 718 welds well when using matching filler metals and proper pre/post weld thermal control; but welded regions often require local heat treatment to restore required properties — for parts requiring full mechanical values, engineered welding procedures and a post-weld aging cycle are essential.

• Cold forming: limited due to high strength and reduced ductility in the aged condition — most forming is done prior to final aging.

Non-destructive testing (UT/MT) and chemical analysis are standard acceptance checks for critical components.

Corrosion resistance and service environments

Alloy 718 offers good resistance to many forms of corrosion (oxidation, pitting to moderate chloride levels) and retains strength at temperatures up to roughly 650–700 °C depending on load and time. It is widely used where mechanical strength under moderate corrosive conditions is needed (aerospace engine components, downhole oil & gas components, springs and fasteners). For aggressive chloride or caustic environments, alternate alloys (Hastelloy, 625, C-276) may outperform 718; material selection must balance mechanical requirements and corrosion exposures.

Typical industry uses and examples

AMS 5663 (Inconel 718, aged bar/forgings) finds application across sectors:

• Aerospace: turbine disks, bolts, critical fasteners where high static strength and creep resistance are required.

• Gas turbines / power generation: shafts, seals, and components exposed to high stress at elevated temperatures.

• Oil & Gas: high-strength downhole tools, springs, and components for MWD/LWD tools and safety valves — when sour service ratings are needed, review API or specialty variants.

• Industrial: high-performance fasteners, pump shafts, and components where a combination of corrosion resistance and high strength is critical.

Real procurement practice: when specifying AMS 5663 material for service, include required NDT levels, MTR traceability, acceptance hardness and test coupon requirements.

Procurement, quality control and traceability

When buying AMS 5663 material, require:

1. Full MTR (mill test report) showing chemical analysis and mechanical test results tied to heat/lot.

2. Hardness test results (Brinell or equivalent) that meet the AMS 5663 minima.

3. Melting process declaration (e.g., VIM/VAR) — many critical aerospace parts require multiple melting steps.

4. Size and finish callouts consistent with AMS limits (max cross-section etc).

5. NDT and acceptance testing as specified by your drawing (UT, MT, PMI where required).

If parts will be welded or further heat treated, agree on who performs final aging and the responsibility for final acceptance.

2025 global price comparison — pragmatic supplier snapshot

Caveat: specialty alloy pricing fluctuates with nickel markets, alloy surcharges, mill form, certification level (aerospace vs industrial), and order quantity. The table below presents industry reported 2025 ranges useful for ballpark procurement planning — always request quotes and confirm lead times and certification cost.

Interpretation and procurement tip: If your application needs AMS/AS9100 traceability, special melting and aerospace paperwork, budget toward the upper half of the ranges above. For industrial, non-critical parts, China and India suppliers often price lower but verify mill certificates and process claims.

Why choose MWAlloys for AMS 5663 material (supply proposition)

At MWAlloys we specialize in high-performance nickel and specialty alloy supply from China with an emphasis on:

• Factory pricing — we supply directly from mill/factory sources (100% factory-price advantage) to reduce distributor markup.

• Fast stock delivery — selected sizes kept in inventory for same-week dispatch; custom forgings and larger orders handled with defined lead times.

• Certification options — standard MTR, PMI on request, and support for extended inspection packages for aerospace or oil & gas.

• Technical support — metallurgical advisory for machining, heat treatment and part acceptance to reduce downstream risk.

If you need AMS 5663 bars or forgings, MWAlloys can provide a quotation with certified MTRs, photographs, and real stock availability wrapped into a clear lead-time and freight solution.

FAQs

1. Is AMS 5663 the same as Inconel 718?
   AMS 5663 covers Alloy 718 in the aged (precipitation-hardened) bar/forging condition. “Inconel 718” and UNS N07718 are equivalent alloy identifiers.

2. Why order AMS 5663 instead of AMS 5662?
   AMS 5663 material arrives already aged and ready for high-strength service; AMS 5662 is typically solution-treated (softer) and is preferred if heavy machining before final aging is planned.

3. What hardness should I expect from AMS 5663 material?
   Typical AMS 5663 aged condition calls for a minimum ~331 HB; always verify the MTR for hardness values.

4. What density should I use for mass calculations?
   Use ≈ 8.19 g/cm³ (0.296 lb/in³) for design and weight estimates.

5. Can aged AMS 5663 be welded without property loss?
   Welding is possible but local properties change in the HAZ; re-heat treatment/aging or controlled welding procedures are often needed to meet mechanical requirements for critical parts.

6. What inspection paperwork should I require?
   Specify full MTR, heat number traceability, hardness results, and any requested NDT (UT/MT) or PMI as part of purchase order.

7. Is Alloy 718 corrosion resistant enough for downhole/sour service?
   Alloy 718 has good general corrosion resistance but for aggressive chloride or highly sour environments, consult API/industry sour-service variants or alternative alloys; additional testing and qualification are recommended.

8. How does AMS 5663 machinability compare to annealed 718?
   Machinability is poorer for AMS 5663 (aged) versus annealed; tool life drops and feeds must be adjusted — consider machining in annealed condition where possible.

9. Typical lead times for AMS 5663?
   For stocked sizes, MWAlloys can supply from inventory quickly; custom forgings or certified aerospace lots vary from weeks to months depending on quantity, spec and required paperwork.

10. What price should I budget for 2025?
    See the table above — for budget planning, use $30–80 / kg as a working range, then confirm with quotes that include certification and shipment terms.

Closing advice for engineers and buyers

• Always attach the exact AMS revision and any drawing callouts when requesting quotes (AMS 5663 revision level, NDT requirements, MTR content).

• If final part toughness and fatigue life are critical, ask your supplier for representative test certificates and discuss any required coupon tests or additional heat treatment.

• When possible, contrast a supplier’s melting process (VIM/VAR) and how they control segregation — these details materially affect performance for high-duty parts.

If you’d like, I can: (a) produce a ready-to-send RFQ template for AMS 5663 (including checklist items), or (b) prepare a supplier comparison table for three MWAlloys stock sizes with instant pricing and lead times. Tell me which you prefer and I’ll draft it.

Authoritative references

• SAE AMS 5663 — Nickel Alloy, Corrosion- and Heat-Resistant, Bars and Forgings (SAE MOBILUS entry)
• Special Metals — INCONEL® alloy 718 technical bulletin (manufacturer data)