Comparison of INCONEL 600 sheet and 718 alloy sheet

01.

Inconel 600 sheet is a high-strength nickel-chromium alloy known for its high-temperature oxidation resistance up to 1175°C, making it suitable for heat treatment and chemical environments. In contrast, Inconel 718 sheet is a precipitation-hardening superalloy with exceptional strength, achieving a yield strength of up to 1035 MPa at temperatures up to 650°C, making it ideal for aerospace and gas turbine components. While the 600 alloy sheet offers superior oxidation resistance at extremely high temperatures, the 718 sheet provides higher strength at medium to high temperatures, despite its greater processing difficulty and higher cost.

02.

What are the disadvantages of Inconel 718?

Disadvantages and alternatives of Inconel 718

While Inconel 718 boasts excellent mechanical and corrosion resistance properties, it also has some drawbacks: High cost: Due to its complex manufacturing process, Inconel 718 is expensive. Difficult to process: Its high hardness makes material removal difficult and accelerates tool wear.

Inconel 600 sheet is rolled from a high-performance nickel-chromium-iron alloy (Inconel 600), renowned for its excellent strength retention at high temperatures (up to approximately 1150°C), superior resistance to oxidation, and resistance to chloride stress corrosion cracking. It is specifically designed for manufacturing equipment linings, structural components, heat exchange parts, and containers that require tolerance to extreme high temperatures and corrosive environments. It is a key basic material in the chemical, nuclear power, heat treatment, and aerospace industries, providing crucial support for harsh operating conditions. Its performance far surpasses that of ordinary stainless steel, but its cost and processing difficulty are correspondingly higher.

Inconel 718 sheet is a high-performance sheet rolled from a nickel-chromium-based superalloy (Inconel 718). It achieves precipitation hardening strengthening through the significant addition of elements such as niobium, molybdenum, titanium, and aluminum. Unlike Inconel 600, which primarily focuses on corrosion resistance, the core advantages of the 718 alloy lie in its extremely high strength, excellent fatigue and creep resistance, and the ability to maintain these properties for extended periods within an extreme temperature range of -253°C to 700°C. Therefore, it is mainly used in fields with extremely high requirements for strength and high-temperature structural stability, such as hot-end components of aero engines (turbine disks, casings), aerospace structural components, high-performance racing car components, and high-requirement oil drilling tools. It is a key material that can withstand huge stress and complex thermal cycling environment, and its processing technology is complex and costly.

600/718 INCONEL SHEETS AND PLATES EQUIVALENT GRADES

STANDARD	UNS	AFNOR	GOST	OR	BS	JIS	EN
Inconel 600	N06600	NC15FE11M	МНЖМц 28-2,5-1,5	ЭИ868	NA 13	NCF 600	NiCr15fe
Inconel 718	N07718	–	–	–	–	NCF 718	–

CHEMICAL COMPOSITION OF INCONEL 600/718 SHEETS AND PLATES

Grade	Ni	Fe	C	Mn	Si	Cu	Cr	S	Mo	Co
600	72	6.0/10.0	0.15	1	0.5	0.5	14.0/17.0	0.015	–	–
718	50/55	–	0.08	0.35	0.35	0.3	17/21	0.015	2.8/3.3	1

MECHANICAL PROPERTIES OF INCONEL 600/718 SHEETS AND PLATES

Grade	Tensile(psi)	.2% Yield (psi)	Elongation (%)
600	95,000	45,000	40%
718	1,50,000	1,20,000	20%

Feature	Inconel 600	Inconel 718
Key Property	High-temperature oxidation resistance	High yield and tensile strength
Typical Applications	Heat-treating furnaces, chemical and nuclear exchangers	Jet engines, gas turbines, nuclear reactor components
Max Service Temp	Up to 1175°C	Up to 650°C
Strength	Lower strength compared to 718	Significantly higher strength, up to 1035 MPa yield strength
Fabrication	Good weldability and machinability (moderate)	Challenging to machine due to high hardness
Cost	More cost-effective	More expensive due to complex production