Characteristics of Inconel 718

Superalloys were created because there were commercial and industrial needs that pure metals and traditional alloys could not fulfill. Like all alloys, Superalloys optimize the natural strengths of selected materials in order to achieve high performance and corrosion resistant reliability, even at temperatures exceeding 1000F. Superalloys can be divided into several different categories and are often identified by brand names from various manufacturers depending on the primary elements of the final alloy. Some common nickel-based superalloys include Inconel, Incoloy, and Monel.

A widely used nickel-base superalloy is UNS N07718, which is also commonly known as Inconel 718. All Inconel alloys are comprised of at least 50% of nickel. For Inconel 718, nickel accounts for 55% max of the final alloy. Chromium (Cr) is the secondary material for Inconel 718, and accounts for 17.0 – 21.0% of the final alloy in mass. The rest of the final alloy consists of various materials including measurable a mixture of both Niobium (Nb) and tantalum (Ta, amounts of iron (Fe), and molybdenum (Mo), and). Trace amounts of silicon (Si), cobalt (Co), aluminum (Al), titanium (Ti) and other materials are also found in Inconel 718.

These elements are used to enhance specific traits to Inconel 718. For example, Chromium offers great corrosion resistance to water, acid and other natural elements. The use of niobium and tantalum provides the final alloy with enhanced mechanical properties. The use of molybdenum aids in both resistance to corrosion and overall alloy strength, but also helps make Inconel 718 more suitable for welding.

Element Proportion (Mass %)

Alloy (UNS) Ni Fe Si C S Mg Al Ti Cr Mo Nb & Ta Co P B Cu
N07718 50.0 – 55.0 Balance* 0.35 max 0.08 max 0.015 max 0.35 max 0.20 – 0.80 0.65 – 1.15 17.0 – 21.0 2.80 – 3.30 4.75 – 5.50 1.0 max 0.015 max 0.006 max 0.30 max
*Reference to the ‘balance’ of a composition does not guarantee this is exclusively of the element mentioned but that it predominates and others are present only in minimal quantities.

Inconel 718 is known for having incredible strength. In fact, Inconel 718 is almost twice as strong as Inconel 625, which is another Inconel alloy that continues to be in high demand for many industrial sectors. Inconel 718 can withstand immense pressure and possesses high resistance to corrosion from the elements, which includes prolonged exposure to saltwater and oxygen.

Because of these characteristics, Inconel 718 is in high demand for many different sectors. Several industries that require superalloys include aircraft engines, commercial space applications, oil and gas, power generation, chemical and petrochemical processing and anywhere else there may be an application within a harsh environment.

Inconel 718 Forging Applications

Given the characteristics of Inconel 718, it is a popular choice for various forging applications. Inconel 718 can be used to form parts that come in many different shapes.

Inconel 718 can be formed into simple part shapes in open die forging applications including bars and blocks, disks, stepped-shafts as well as other simple open-die shapes. Semi-closed die or closed-die forging applications can also be used on Inconel 718 parts that have higher volumes, require finer tolerances and less material waste on the completed forged part, or have specific grain flow requirements for enhanced mechanical properties.

Inconel forging parts are used in various industrial applications. The aerospace sector especially relies on Inconel 718 forged parts for many different components, including aircraft and jet engines, fuel lines, nuclear fuel parts, and other rocket components.

Inconel 718 forged parts are also used for the following applications:

  • Turbine engine parts, such as compressor casings, discs, ducting and fan blades
  • High temperature bolts and fasteners
  • Turbocharger rotors and seals
  • Electric submersible well pump motor shafts
  • Chemical processing and pressure vessels

At Weldaloy Specialty Forgings, we are committed to providing customers with quality Inconel 718 parts. We offer open-die and semi-closed-die forging capabilities, along with heat treat and machining. We provide metallurgical services for projects that require it, which include specifications on grain size and grain direction, to ensure that our finished products meet your mechanical and other testing standards. Our team of engineers and quality personnel oversee our Inconel 718 parts at every step of production and testing to ensure the quality of our products.

Below is a general guideline for Weldaloy’s Inconel 718 forging capabilities. Please contact us for the specific requirements of your Inconel 718 forged parts.

ITEM OUR CAPABILITIES
ROLLED RINGS 50” MAX OD
FLAT BAR / BLOCKS 16” MAX
CYLINDERS / SLEEVES 40” MAX OD
DISKS/ HUBS / SPECIAL SHAPES 24” MAX OD/WIDTH
ROUND / SHAFTS 12” MAX OD/WIDTH
CUSTOM DIE PRESS 24’’ MAX OD/WIDTH

Weldaloy Specialty Forgings stands ready to be your Inconel 718 or Inconel 625 forging partner.

Send us your request for quote today – and discover the Weldaloy Specialty Forgings difference.

quoting@weldaloy.com