Comparison of Inconel 600 and Nickel Alloy 718 round bars

Inconel 600 round bars are a versatile nickel-chromium alloy suitable for general high-temperature corrosive environments; while nickel alloy 718 bars (Inconel 718) are precipitation-hardening superalloys with tensile strength/creep strength far exceeding that of Inconel 600 round bars from low to high temperatures, making them an ideal choice for aerospace (turbine engines, rockets), but they are more expensive and more difficult to process. The main differences lie in strength (718) versus versatility/cost (600).

What is the composition of Inconel 718 round bars?

Inconel 718 round bars are nickel-chromium alloy bars with a nickel content of up to 55%. Their composition includes 17% chromium, 4.9% niobium, at least 6.6% iron, and aluminum, boron, carbon, cobalt, copper, manganese, phosphorus, lead, sulfur, and silicon.

Inconel 600 bars are rod-shaped profiles made from the nickel-chromium-iron alloy (Inconel 600) through hot rolling or cold drawing processes. They possess the alloy's signature high-temperature oxidation resistance (up to approximately 1150°C), excellent resistance to chloride ion stress corrosion, and good mechanical properties. They are primarily used in the manufacture and processing of critical components that need to operate in extremely high-temperature and corrosive environments, such as shafts, valve parts, furnace components, corrosion-resistant screws, and experimental equipment accessories. They provide highly reliable raw materials for the chemical, nuclear power, heat treatment, and aerospace industries. While offering good machinability, their cost is significantly higher than ordinary stainless steel bars.

Inconel 718 bars are rod-shaped profiles made from a precipitation-hardening nickel-based superalloy (Inconel 718). Their core value lies in the addition of elements such as niobium and molybdenum, which allows them to maintain ultra-high strength and excellent creep and fatigue resistance at temperatures up to approximately 700°C. It is specifically designed for manufacturing and processing critical structural components that withstand extreme stress, high temperatures, and complex loads, such as aero-engine turbine shafts, high-strength fasteners, oil drilling tools, racing car transmission components, and high-performance molds. It is a top-tier raw material in the aerospace, energy, and high-end manufacturing fields that requires materials to have both excellent high-temperature mechanical properties and good corrosion resistance. Its heat treatment and processing technology is complex and costly.

Comparison of chemical composition (weight percentage) of Inconel 600 and 718 alloy rods

Alloy	Ni	Cr	Fe	Mo	Co	Nb	Al	Ti	Mn	Si	C	Other
Inconel 600	≥72	14-17	6-10	–	–	–	–	–	≤1	≤0.5	≤0.15	Cu ≤0.5, S ≤0.015
Inconel 718	50-55	17-21	Balance	2.8-3.3	≤1	4.75-5.5	0.2-0.8	0.65-1.15	≤0.35	≤0.35	≤0.08	B ≤0.006, Cu ≤0.3

Comparison of mechanical properties of Inconel 600 and 718 alloy bars (annealed state)

Alloy	Tensile Strength (MPa)	Yield Strength (MPa)	Elongation (%)	Hardness (Rockwell)
Inconel 600	550 (80 ksi)	240 (35 ksi)	30%	B80
Inconel 718	1240 (180 ksi)	1035 (150 ksi)	12%	C35

Inconel 600 and Inconel 718 bar product forms and ASTM standards

Alloy	Pipes & Tubes	Plates, Sheets & Strips	Bars & Rods	Forgings	Rings
Inconel 600	ASTM B167	ASTM B168	ASTM B166	ASTM B564	Custom
Inconel 718	ASTM B983	ASTM B670	ASTM B637	ASTM B637	AMS 5662

Heat treatment process for Inconel 600 and 718 alloy bars

Alloy	Solution Annealing Temperature	Cooling Method	Precipitation Hardening (if applicable)
Inconel 600	1010–1150°C (1850–2100°F)	Air cool	Not applicable
Inconel 718	980°C (1800°F) for 1 hr, then 720°C (1325°F) for 8 hrs	Air cool	Yes - age-hardened for high-strength

Welding performance of Inconel 600 and 718 alloy bars

Alloy	Weldability Rating	Recommended Welding Process	Post-Weld Heat Treatment
Inconel 600	Excellent	GTAW (TIG), GMAW (MIG), SMAW (Stick)	Not required
Inconel 718	Moderate (susceptible to cracking)	GTAW, Electron Beam, Laser	Solution annealing is recommended after welding

Key Comparison Points

Strength: Alloy 718 significantly outperforms due to its precipitation hardening properties.

Temperature: 718 performs better over a wider range of extreme temperatures.

Cost/Machinability: 600 is generally cheaper and easier to machine; 718's high hardness makes it more expensive and more difficult to machine.

Applications: 600 is suitable for general high-temperature and corrosive environments; 718 is suitable for applications requiring extremely high strength.

Why Choose Gnee as Your Nickel-Based Alloy Supplier

✅ Over 18 years of export experience, products sold to more than 80 countries

✅ Certified by ISO, SGS, and BV

✅ Global inventory of Inconel, Hastelloy, Incoloy, and Monel alloy tubing, plates, and bars

✅ Custom processing services available – including cutting, polishing, CNC machining, and packaging

✅ Fast delivery within 7-15 days, supported by global logistics partners

📦 Packaging and Shipping

All stainless steel products are packaged using the following methods:

Wooden pallets or crates

Moisture-proof packaging

Labels with furnace number, standard, and size labels

Shipped worldwide by sea, air, or express