Nickel-chromium alloy, INCONEL 718, solution treated & aged

INCONEL 718, solution treated & aged, Designation

Wrought Ni-Cr alloy: Inconel 718, STA
Condition	Solution treated & aged
UNS number	N07718
US name	ASTM Grade N07718; AMS 5662, 5663, 5664, 5832, 5914, 5962, 5596, 5597, 5950
EN name	NiCr19NbMo
EN number	2.4668
ISO name	ISO 9723-9725

INCONEL 718, solution treated & aged, Tradenames

INCONEL 718, Special Metals Corp. (USA)

HAYNES 718, Haynes International Inc. (USA)

ALTEMP 718 Solution treated, ATI Allegheny Ludlum (USA)

PYROMET ALLOY 718, Carpenter Technology Corp. (USA)

MSRR 7132, MSRR 7228, Rolls Royce (UK)

WA2225.3, MTU (GERMANY)

PWA 649, Pratt & Whitney (USA)

CPW407, Pratt & Whitney (USA)

DMD423.32, SNECMA (FRANCE)

C50TF89, B50T68, B50TF16A, GE (USA)

LA213, Turbomeca (FRANCE)

EMS 55458, Garrett (USA)

SUPERMET 718, Firth Rixson (USA)

INCONEL 718, solution treated & aged, Typical uses

Aerospace, high temperature applications, heating elements, furnace parts, resistors, electronic parts, combustion systems, after- burners, fuel nozzles, chemical processing equipment, pulp and paper manufacture, marine architecture, nuclear reactors

INCONEL 718, solution treated & aged, Composition detail

Al (aluminum)	0.2	–	0.8	%
B (boron)	0	–	0.006	%
C (carbon)	0	–	0.08	%
Co (cobalt)	0	–	1	%
Cr (chromium)	17	–	21	%
Cu (copper)	0	–	0.3	%
Fe (iron)	11.1	–	24.6	%
Mn (manganese)	0	–	0.35	%
Mo (molybdenum)	2.8	–	3.3	%
Nb (niobium)	2.38	–	2.75	%
Ni (nickel)	41.5	–	63.5	%
P (phosphorus)	0	–	0.015	%
S (sulfur)	0	–	0.015	%
Si (silicon)	0	–	0.35	%
Ta (tantalum)	2.38	–	2.75	%
Ti (titanium)	0.65	–	1.15	%

INCONEL 718, solution treated & aged, Physical properties

Density

8.18

–

8.26

g/cm3

INCONEL 718, solution treated & aged, Mechanical properties

Young’s modulus	198	–	208	GPa
Specific stiffness	24.1	–	25.3	MN.m/kg
Yield strength (elastic limit)	1000	–	1110	MPa
Tensile strength	1170	–	1320	MPa
Specific strength	122	–	134	kN.m/kg
Elongation	10	–	15	% strain
Compressive strength	931	–	1150	MPa
Flexural modulus	198	–	208	GPa
Flexural strength (modulus of rupture)	1000	–	1110	MPa
Shear modulus	77	–	80.9	GPa
Bulk modulus	157	–	173	GPa
Poisson’s ratio	0.29	–	0.302
Shape factor	16
Hardness – Vickers	400	–	500	HV
Hardness – Rockwell B	112	–	117	HRB
Hardness – Rockwell C	41	–	49	HRC
Hardness – Brinell	379	–	471	HB
Elastic stored energy (springs)	2460	–	3010	kJ/m3
Fatigue strength at 10^7 cycles	485	–	755	MPa
Fatigue strength model (stress range) Parameters: Stress Ratio = -1, Number of Cycles = 1e7cycles	473	–	774	MPa

INCONEL 718, solution treated & aged, Impact & fracture properties

Fracture toughness	119	–	130	MPa.m0.5
Toughness (G)	69.2	–	83.6	kJ/m2

INCONEL 718, solution treated & aged, Thermal properties

Melting point	1260	–	1340	°C
Maximum service temperature	632	–	705	°C
Minimum service temperature	-273			°C
Thermal conductivity	11.6	–	12.6	W/m.°C
Specific heat capacity	440	–	458	J/kg.°C
Thermal expansion coefficient	12.8	–	13.4	µstrain/°C
Thermal shock resistance	372	–	420	°C
Thermal distortion resistance	0.879	–	0.966	MW/m
Latent heat of fusion	275	–	300	kJ/kg

INCONEL 718, solution treated & aged, Electrical properties

Electrical resistivity	115	–	125	µohm.cm
Electrical conductivity	1.38	–	1.5	%IACS
Galvanic potential	-0.05	–	0.03	V

INCONEL 718, solution treated & aged, Magnetic properties

Magnetic type

Non-magnetic

INCONEL 718, solution treated & aged, Optical, aesthetic and acoustic properties

Transparency	Opaque
Acoustic velocity	4910	–	5030	m/s
Mechanical loss coefficient (tan delta)	1e-4	–	3e-4

INCONEL 718, solution treated & aged, Processing properties

Metal casting	Unsuitable
Metal cold forming	Acceptable
Metal hot forming	Limited use
Metal press forming	Acceptable
Metal deep drawing	Limited use
Machining speed	3.05 m/min
Weldability Notes: Preheating is not required, post weld heat treatment is required	Good
Weldability – MIG	Good
Weldability – plasma	Good
Weldability – SAW	Good
Weldability – TIG	Good
Brazeability	Good

INCONEL 718, solution treated & aged, Durability

Water (fresh)	Excellent
Water (salt)	Excellent
Weak acids	Excellent
Strong acids	Excellent
Weak alkalis	Excellent
Strong alkalis	Excellent
Organic solvents	Excellent
Oxidation at 500C	Excellent
UV radiation (sunlight)	Excellent
Galling resistance (adhesive wear) Notes: Bronze or zinc alloy dies should be used to minimize galling.	Limited use
Flammability	Non-flammable

INCONEL 718, solution treated & aged, Corrosion resistance

Stress corrosion cracking Note: Rated in chloride; Other susceptible environments: Hydroxide	Not susceptible
Intergranular (weld line) corrosion	Excellent
Inorganic acids	Excellent
Organic acids	Excellent
Alkalis	Excellent
Humidity / water	Excellent
Sea water	Excellent
Sour oil and gas	Excellent

INCONEL 718, solution treated & aged, Notes

Warning

All nickel compounds should be regarded as toxic.  Some can cause cancer and/or fetal abnormalities.

INCONEL 718, solution treated & aged, Standards with similar compositions

USA: ERNiFeCr-2 to AWS A5.14/A5.14M, N07718 to ASTM B637, N07718 to ASTM B670, UNS N07718, UNS N07719

Tradenames: ALLOY 718, ALTEMP 718, ELECTRALLOY TOOLWARE® 718, EMVAC 718, HAYNES ALLOY NO. 718, LSS 718 EP, UNITEMP 718, NICROFER 5219NB-ALLOY 718, UDIMET 718 (WROUGHT)