Inconel 702 (700)

• INCONEL 700 exhibits excellent age-hardenability and can resist both heat & corrosion. It is furthermore known for its exceptional stress-rupture characteristics. Its strength can be increased even further by a variety of heat treatment techniques and can be hardened to reach high-yield strength levels. INCONEL 700 is a versatile material, making it suitable for a range of applications. The alloy is usually produced by AOD /VDVIM followed by electroslag refining (ESR) / VAR if necessary for special purpose. Bars and, where applicable, forgings are subjected to ultrasonic examination based on the different levels.
• UNS N07702 is an alloy made of nickel, chromium, and iron. It has a high strength-to-weight ratio, excellent corrosion resistance, and good heat resistance. It is one of the most popular alloys used in various industries, such as aerospace, power generation, and chemical processing. This article will discuss the composition, properties, uses, and welding of Inconel 702.

Standard Specification 702

• ASTM B446 / ASME SB446
• ASTM B443 / ASME SB443
• ASTM B564 / ASME SB564
• ASTM F467 / F467M
• ASTM F468 / F468M
• AMS 5666
• BS 3076
• Alloy 702
• UNS N06702
• DIN / EN / Werkstoff No. 2.4856

 Chemical Composition Inconel 700 and 702

  Table 1 - Chemical Composition Inconel 700

 Table 2 - Chemical Composition Inconel 702

 Applications of Inconel 702

Superalloy is widely used to produce high-temperature components for gas turbines in the field of aviation, naval vessels and industry, such as turbine blades, guide blades, turbine disc, high-pressure compressor disc, combustors, and also the production of energy conversion devices, such as aerospace craft, rocket motor, nuclear reactor, petrochemical equipment, coaly transforming and so on. The alloy is usually produced by AOD / VD / VIM followed by electroslag refining (ESR) / VAR if necessary for special purposes. Bars and, where applicable, forgings are subjected to ultrasonic examination based on the different levels according to the buyers' requirements. Bars are usually supplied with bright surfaces in the solution-annealed condition. Final heat treatment - solution + Aged or Double aged.

 Physical Properties

In terms of physical properties, Inconel 702 offers superior thermal stability with a melting point range between 1320°C – 1350°C. Its density is 8 g/cm3, which makes it relatively light when compared to other metals with similar characteristics, such as titanium or stainless steel alloys. The modulus of elasticity for this alloy is 200 GPa which provides it with good formability in extreme temperatures and environments.

Table 3 - Physical Properties Inconel 700

 Table 3a - Physical Properties Inconel 702

  Mechanical Properties

The mechanical properties of Inconel 702 are excellent. It has a high tensile strength that can reach up to 810 MPa at room temperature. The yield strength is also impressive at 690 MPa, while its elongation rate stands at 35%. Additionally, it has good fatigue strength, which makes it ideal for applications that require frequent loading cycles, such as aircraft components or heavy machinery parts. For more details see Table 4 below

 Table 4 -  Nominal Room-Temperature Mechanical Properties

Corrosion Resistance

In addition to its heat resistance capabilities, Inconel 702 also has great corrosion resistance, which allows it to stand up against harsh environments without fear of damage from oxidation or rust over time. This makes it ideal for use in applications such as marine engines and oil refineries where exposure to corrosive elements is inevitable on a daily basis without risk of failure due to material degradation over time.

Heat Treatment

In order to achieve optimal performance from this alloy, it must be treated using specific heat treatments depending on the application that they will be used in afterwards; however, this treatment should only be done by experienced professionals who have the necessary knowledge and equipment available in order to do so safely and correctly without damaging the material itself during the process.

 Machinability (Recommendations) 

Additionally, machining this material requires special tools due to its hardness, so again only experienced personnel should attempt machining operations involving this metal alloy if possible.

Machining Inconel

Machining Inconel requires high cutting forces and a highly developed skill set to ensure it is done correctly on a consistent, repeatable basis. To properly work with Inconel takes an understanding of its properties and how to compensate for its limitations. Machining tips include:

• Check tooling frequently for signs of wear
• Start with a solutionized piece of metal
• Use ceramic cutting tools for continuous cuts
• Avoid pecking when drilling Inconel
• Endmill with more flutes
• Drill with replaceable tips
• Use cobalt roughers for
• Think rigidity—fixture, machine tooling

Forging Inconel Alloys

Inconel is widely used in forging industries for quality and oxidation-resistant end products. That’s because corrosion is among the most common problems within industries using forging materials. Manufacturers tried using Inconel in various applications and found it both practical and useful, so they’ve continued using it.

Forging presses metal under great pressure into high-tensile strength components. This manufacturing process refines the grain structure and improves the physical properties— ductility, toughness, and strength—of metal so that the grain flow can be oriented in the direction of principal stresses encountered in actual use.

Critical advantages of forging are:

• Beats casting or machining bar stock
• Stronger parts than other metalworking processes
• Highly shapeable into almost any product
• Versatile enough for use in any industry
• Cost-effective for manufacturing in large quantities

Welding of Inconel 702

When welding with this particular alloy, special care must be taken into consideration prior to doing so since welding parameters vary depending on the filler material being used; however, some general considerations need to be taken into account no matter what type of filler materials being used such as preheating before welding if possible so that any residual stresses created during fabrication can relieved before welding begins as well as taking extra care when removing slag from welds since excessive heat input could cause damage.

Successfully welded by common fusion and resistance methods, this alloy should not be joined by oxyacetylene welding. AWS E/ER630 filler metal is recommended if required.

Is Inconel Considered Steel?

Inconel is not considered steel or stainless steel. While stainless steel and Inconel both have silver finishes and use a numbering system for alloys and strengths, they are different in quality, characteristics, uses, and weight.
Inconel features a nickel, chromium, and molybdenum composition, resists corrosion and pitting and is available in several different alloys. Inconel costs more than stainless steel and can be superficially textured for a matte finish or smoothed for a shiny finish.
Stainless steel features a carbon, manganese, phosphorus, sulfur, silicon, chromium, and nickel composition; and a protective oxide layer that can be damaged by continuous exposure to extreme conditions. It’s available in several different grades.
Stainless steel is also heavier than Inconel alloys. Inconel jewelry, for example, looks like stainless steel but feels a lot like aluminium in weight. Stainless steel also doesn’t withstand heat as well as Inconel. That makes Inconel better suited for certain industrial products than stainless steel.

Conclusion

In conclusion, Inconel 702 is an incredibly versatile metal alloy thanks to its excellent mechanical, physical, and chemical properties, making it suitable for use in many different industries ranging from aerospace engineering to power generation plants and chemical processing facilities. Its high strength-to-weight ratio allows It to stand extreme temperatures without losing its structural integrity, while its corrosion resistance properties allow it to be used in marine applications without fear of rust formation over time. Finally, the ability to machine and weld with this alloy makes the site even more attractive for industrial-scale use as long as the proper protocol is followed during these operations by experienced professionals to prevent damage or thermal distortion of the material itself.