Views: 24 Author: Site Editor Publish Time: 2025-07-09 Origin: Site
JN Company supplies premium Inconel 718 in versatile forms, including sheet, plate, bar, round bar, tube, pipe, wire, fasteners, and pipe fittings. We guarantee material quality compliant with AMS 5662/5663 standards, backed by full traceability and precision heat treatment.
Enjoy competitive pricing with volume discounts on raw stock and engineered components. Our services feature low MOQs, rapid prototyping, and global logistics support. Trust JN for reliable 718 Inconel solutions tailored for aerospace, oil & gas, and high-stress applications.
718 is a nickel-chromium superalloy renowned for its exceptional strength, corrosion resistance, and versatility in extreme environments. Also called 718 Inconel, it retains mechanical properties at temperatures up to 700°C. This overview covers its composition, properties, forms, pricing, and applications.
718 primarily composed of Nickel and Chromium, it forms a solid foundation. Chromium provides excellent oxidation and corrosion resistance. Crucially, significant additions of Niobium and smaller amounts of Molybdenum, Titanium, and Aluminum enable a powerful strengthening mechanism called precipitation hardening.
Fe is also balance, making it a more cost-effective than some purer nickel alloys. Understanding the 718 composition or 718 Inconel composition is key before you buy:
Inconel 718 (UNS N07718) | |||||||
C | Si | Mn | P | S | Cr | Ni | Mo |
≤0.08 | ≤0.35 | ≤0.35 | ≤0.015 | ≤0.015 | 17-21 | 50-55 | 2.8-3.3 |
Co | Nb | Al | Ti | B | Mg | Cu | Fe |
≤1.0 | 4.75-5.5 | 0.2-0.8 | 0.65-1.15 | ≤0.006 | - | ≤0.30 | Remain |
Inconel 718 Density: The density of 718 is approximately 0.297 lb/in³ (8.19 g/cm³). This density or 718 Inconel density is a fundamental physical constant for the alloy, important for weight calculations.
Inconel 718 Melting Point: The melting point of 718 Inconel ranges between 2300°F and 2460°F (1260°C and 1350°C). This 718 melting point or melting point defines its upper processing limits and resistance to heat. Its melting temperature is exceptionally high.
Inconel 718 Thermal Conductivity: Thermal conductivity is relatively low, around 6.5 - 11.7 W/m·K depending on temperature. This means heat doesn't flow through it easily, which can be an advantage or disadvantage (heat buildup during machining).
Inconel 718 Hardness: Hardness varies significantly depending on heat treatment. In the annealed condition, it's typically around Rockwell B 85-95. After full aging (precipitation hardening), it achieves impressive hardness, often Rockwell C 35-45 (Inconel 718 hardness, 718 Inconel hardness). This directly impacts wear resistance and machinability.
Inconel 718 Yield Strength: This is a critical measure of its load-bearing capacity. The yield strength of 718 is exceptionally high, typically ≥ 120 ksi (825 MPa) at room temperature, and remains strong even at elevated temperatures.
Tensile Strength: Typically ≥ 150 ksi (1035 MPa) at room temperature after aging.
Elongation: Around 12-20% in the aged condition, indicating good ductility for a high-strength alloy.
JN supplies premium Inconel 718 superalloy in versatile forms including sheet, plate, bar, round bar, tube, pipe, wire, fasteners, and pipe fittings. Enjoy competitive pricing with volume discounts on raw stock and engineered components. Request a quote today at Info@jnalloy.com.
Excellent Strength
Alloy 718 maintains acceptable structural qualities at temperatures as high as 1600 degrees Fahrenheit, offering strength and dependability at very high temperatures. Specifically, Inconel 718's resilience to high temperatures makes it ideal for usage in aircraft, particularly in engine positions.
Oxidation and Corrosion Resistance
The Inconel 718 alloy exhibits exceptional resilience in situations involving extremely high pressure, including gas turbines, rocket engines, and pressure vessels. In order to make Inconel 718 alloy resistant to high oxidation and corrosion, which is typical in many aircraft parts, it can also be precipitation hardened with titanium or aluminum.
Low Expansion Properties
Due to its low coefficient of thermal expansion (260°C), Inconel 718 maintains strength and dimensional stability. Common uses include piping systems for liquid gas storage/transport and molds/tooling for aerospace composite manufacturing.
Creep resistance
Inconel 718 nickel alloy has very good creep resistance. It retains toughness under high stress at temperatures up to 850°C, making it critical for aircraft engine turbine rotors and internal combustion engine exhaust valves.
While strong when annealed, Inconel 718 reaches peak performance via precipitation hardening/aging heat treatment:
Solution Annealing: Typically performed around 1700-1850°F, followed by rapid cooling. This dissolves the strengthening phases and softens the alloy for fabrication.
Aging: A two-step process is standard:
Hold at 1325°F ±25°F for 8 hours.
Furnace cool to 1150°F ±25°F.
Hold at 1150°F ±25°F for a total aging time of 18 hours including cool-down time.
Air cool.
Aging produces fine γ' and γ'' phases within the matrix, substantially increasing strength and hardness while retaining good toughness. Precise control of the heat treatment is paramount for achieving the desired Inconel 718 material properties.
Composition Comparison
Inconel 718 Composition: Higher Fe, Nb, Ti, Al. Forms the γ'' (Ni₃Nb) phase during heat treatment, enabling exceptional precipitation hardening. This gives it superior yield strength and tensile strength.
Inconel 625 Composition: Higher Ni and Mo, with some Nb. Achieves strength primarily through solution strengthening. It is typically used in the annealed condition and does not require aging for corrosion resistance.
Mechanical Properties Comparison
Strength: Inconel 718 has significantly higher yield strength up to 1100 MPa / 160 ksi at RT and tensile strength than Inconel 625.
Creep and Fatigue: Inconel 625 offers superior creep resistance and fatigue strength at temperatures above 700°C due to its high Mo content and solution-strengthened structure. Inconel 718 excels in creep and fatigue below 650°C but loses significant strength above this as the γ'' phase dissolves.
Hardness: Aged Inconel 718 hardness 35-47 HRC is higher than annealed Inconel 625 hardness.
Corrosion Resistance Comparison
Inconel 625 is generally superior, particularly for seawater, brine, and acidic chloride environments. Oxidation resistance at very high temperatures.
Inconel 718 offers very good resistance to:
High-temperature oxidation and sulfidation.
Acidic environments.
Stress-corrosion cracking in chloride solutions.
Fabrication Comparison
Machining: Machining Inconel 718 is very difficult. It requires rigid setups, sharp carbide tools, low speeds, high feeds, and ample coolant. Machining Inconel 625 is easier due to less work hardening.
Welding: Inconel 718 has excellent weldability without post-weld heat treatment cracking, a major advantage over many other high-strength superalloys. Inconel 625 is also readily weldable but can be more susceptible to microfissuring in highly restrained joints.
Heat Treatment: Inconel 718 requires a specific solution annealing and aging heat treatment to achieve its peak strength. Inconel 625 is typically used in the solution-annealed condition; aging is not standard method and can reduce ductility.
High Temperature Performance Comparison
For high yield and fatigue strength up to 650-700°C, Inconel 718 is ideal.
For corrosion/oxidation resistance or moderate strength from above 700°C up to 980°C, Inconel 625 performs better.
Both alloys perform well at low temperatures.
The price of Inconel 718 is significantly higher than that of ordinary stainless steel. Its price changes are mainly related to raw material costs, product form, size, and purchase quantity.
Inconel 718 price per kg or Inconel 718 price per pound are common queries. While exact current prices require supplier quotes, expect costs to be several times higher than 304 stainless steel. The following is a price list of different 718 products from JN Alloys:
Form | Price per kg | Price per Pound | Key Influencing Factors |
Inconel 718 Billet/Ingot | 35–50 USD | 16–23 USD | Nickel market volatility, order volume |
Inconel 718 Bar/Round Bar | 40–65 USD | 18–30 USD | Diameter, tolerance, surface finish |
Inconel 718 Sheet/Plate | 45–70 USD | 20–32 USD | Thickness (thin sheet costs more) |
Inconel 718 Tube/Tubing | 55–85 USD | 25–39 USD | Wall thickness, OD precision |
Inconel 718 Wire | 60–90 USD | 27–41 USD | Diameter, spool size |
Inconel 718 Fasteners | 70–120 USD | 32–55 USD | Complexity (e.g., bolts vs. custom nuts) |
Inconel 718 Custom Stamped Parts | 90–200+ USD | 41–90+ USD | Design complexity, tooling, lot size |
Note: The above prices are for reference only. Please contact our sales team for the actual prices.
JN supplies premium Inconel 718 superalloy in versatile forms including sheet, plate, bar, round bar, tube, tubing, wire, fasteners, and pipe fittings. Enjoy competitive pricing with volume discounts on raw stock and engineered components. Request a quote today at Info@jnalloy.com.
