Standard Specification for Precipitation Hardening Bolting (UNS N07718) for high Temperature Service.

This specification covers precipitation hardening alloy Inconel 718 (UNS N07718) Bolting for high temperature service. ASTM A1014 covers imperial sized bolts whereas ASTM A1014M is a complete metric companion. ASTM A1014 prescribes requirements for chemical, mechanical properties, tests, ordering information, heat treament, etc. Starting material used for these high strength bolting should comply with ASTM B637 UNS N07718. BoltPort can manufacture Bolts, Studs Bolts, Screws as per ASTM A1014 UNS N07718 grade specification. We can produce metric sizes from M6 to M100 & imperial sizes from 1/4 inch to 4 inch. Larger sizes can be made to order with customization. BoltPort offers these Inconel 718 bolting duly tested with EN 10204 Type 3.1 Certification.

ASTM A1014 Chemical Requirements

Element UNS N07718 (Inconel 718)
Carbon, max 0.08
Manganese, max 0.35
Silicon, max 0.35
Phosphorus, max 0.015
Sulfur, max 0.015
Chromium 17.00 - 20.00
Cobalt, maxA 1.00
Molybdenum 2.80 - 3.30
Columbium + Tantalum 4.75 - 5.50
Titanium 0.65 - 1.15
Aluminum 0.20 - 0.80
Boron, max 0.006
IronB Remainder
Copper, max 0.30
NickelC 50.00 - 55.00

A If determind
BDetermined arithematically by difference CNickel + Cobalt

ASTM A1014 Mechanical Properties

Tensile and Hardness
Tensile Strength, min, ksi [Mpa] 185 [1275]
Yield Strength, min, ksi [Mpa], 0.2% offset 150 [1035]
Elongation in 2 inch, Or 50mm [4D], min, % 12
Reduction of Area, min, % 15
Hardness, Brinell 331 - 444
Stress Rupture Requirements
Temperature, °F [°C] 1200 [650]
Stress, ksi [Mpa] 100 [690]
Hours, min 23
Elongation in 2 inch, Or 50mm [4D], min, % 5
Elevated Tensile Requirements
Temperature, °F [°C] 1200 [650]
Tensile Strength, min, ksi [Mpa] 145 [1000]
Yield Strength, min, ksi [Mpa], 0.2% offset 125 [860]
Elongation in 2 inch, Or 50mm [4D], min, % 12
Reduction of Area, min, % 15

Heat Treatment

Solution Treatment

Material shall be solution heat treated at temperature within the range of 1725 to 1850°F [940 to 1010°C], held at the selected temperature for a time commensurate with cross sectional thickness, and cooled at a rate equivalent to an air cool or faster.

Precipitation Heat Treatment

Material shall be heated to a temperature of 1235°F [720°C], held at temperature for eight hours minimum, furnace cooled to 1150°F [620°] at 100°F [55°C] per hour, held at temperature for eight hours, and cooled to room temperature. Alternatively, material may be furnace cooled to 1150°F [620°C] at any rate provided the time at 1150°F [620°C] is adjusted so the total precipitation heat treatment time is 18 hours minimum.

Staightening Threads
When straightening is necessary it shall be done after solution treating and prior to agin. Straightening after aging is prohibited. Threads shall be formed by rolling in one pass after oxides have been removed from the area to be threaded.

Dimensions and Tolerance

Full heat treated material shall meet the dimensional requirements of specification ASTM B637 for UNS N07718.