Incoloy 825 – Properties, Applications, Fabrication, Machinability and Weldability of Incoloy 825

2022-05-28 13:56:22 By : Mr. Patrick Lin

We use cookies to enhance your experience. By continuing to browse this site you agree to our use of cookies. More info.

Incoloy 825 is highly resistant to corrosion. It has a high nickel content, sufficient to resist chloride ion stress corrosion cracking, and a very stable austenite structure. The levels of molybdenum and copper enable the alloy to resist reducing agents and acids. Chromium gives resistance to oxidising conditions, such as nitric acid solutions, nitrates and oxidising salts. The alloy is titanium stabilised to resist pitting and intergranular attack after fabrication, particularly welding, which includes heating in the critical sensitisation temperature range (650°C – 760°C).

Alloy 825 offers exceptional resistance to corrosion by sulphuric and phosphoric acids and is often the most cost effective alloy in sulphuric acid service.

Austral Wright Metals can supply this alloy as plate, sheet, strip, bar, rod, wire, tube, pipe, fittings, fasteners.

Incoloy 825 is approved for pressure vessel operating temperatures up to 525°C (AS1210, AS4041), 538°C (ASME Boiler & Pressure Vessel Code, Sections I, III, VIII, IX, Cases 1936, N-188). Brittle phases may form in alloy 825 at temperatures above ~ 540°C, so it is not normally used at these temperatures, where creep-rupture properties would be design factors.

Typical Applications of Incoloy Alloy 825 include:

Table 1. Chemical composition of Incoloy Alloy 825 (ASTM B163 – Heat exchanger tube)

Table 2. Typical room temperature tensile properties (not for design. Consult the relevant material or product specification for design values)

Figure 1. High temperature tensile properties of annealed Incoloy 825 bar.

The outstanding property of Incoloy 825 is its corrosion resistance. In reducing & oxidising conditions, Incoloy 825 resists general corrosion, pitting & crevice corrosion, intergranular corrosion and stress corrosion cracking. It is particularly useful in sulphuric & phosphoric acids, sulphur containing flue gases, sour gas and oil wells and sea water.

Figure 2. Isocorrosion chart in laboratory pure sulphuric acid.

Incoloy 825 can be readily hot or cold worked. Hot working should be in the range 870 – 1180°C, finishing at 870 – 980°C. For maximum corrosion resistance hot worked parts should be stabilise annealed before use. The alloy is easier to cold form than stainless steels.

Incoloy 825 is classed as a ‘C’ alloy, and is reasonably easy to machine.

The alloy is readily weldable by the normal processes (GMAW (MIG), GTAW (TIG), SMAW (manual), SAW). The joint must be clean to avoid contamination of the weld pool.

Table 5. A guide to welding consumables to be used with Incoloy Alloy 825 under various conditions.

Incoloy 825 is stabilise annealed at 940°C. The softest structure is obtained at 980°C. Sections heavier than sheet, strip and wire should be quenched to avoid sensitisation.

Please consult Austral Wright Metals for specific advice on your application.

Table 6. ASM specifications for Incoloy Alloy 825.

Seamless Nickel and Nickel Alloy Condenser and Heat-Exchanger Tubes

Nickel-Iron-Chromium-Molybdenum-Copper Alloy (UNS N08825 and N08221)* Seamless Pipe and Tube

Ni-Fe-Cr-Mo-Cu Alloy (UNS N08825 and UNS N08221)* Plate, Sheet, and Strip

Welded UNS N06625 and UNS N08825 Alloy Tubes

Nickel-Alloy (UNS N06625 and N08825) Welded Pipe

General Requirements for Nickel and Nickel Alloy Welded Tube

Table 7. Other international grades that are equivalent to Incoloy Alloy 825.

This information has been sourced, reviewed and adapted from materials provided by Austral Wright Metals - Ferrous, Non-Ferrous and High Performance Alloys .

For more information on this source, please visit Austral Wright Metals - Ferrous, Non-Ferrous and High Performance Alloys .

Please use one of the following formats to cite this article in your essay, paper or report:

Austral Wright Metals - Ferrous, Non-Ferrous and High Performance Alloys. (2020, June 10). Incoloy 825 – Properties, Applications, Fabrication, Machinability and Weldability of Incoloy 825. AZoM. Retrieved on May 28, 2022 from https://www.azom.com/article.aspx?ArticleID=4245.

Austral Wright Metals - Ferrous, Non-Ferrous and High Performance Alloys. "Incoloy 825 – Properties, Applications, Fabrication, Machinability and Weldability of Incoloy 825". AZoM. 28 May 2022. <https://www.azom.com/article.aspx?ArticleID=4245>.

Austral Wright Metals - Ferrous, Non-Ferrous and High Performance Alloys. "Incoloy 825 – Properties, Applications, Fabrication, Machinability and Weldability of Incoloy 825". AZoM. https://www.azom.com/article.aspx?ArticleID=4245. (accessed May 28, 2022).

Austral Wright Metals - Ferrous, Non-Ferrous and High Performance Alloys. 2020. Incoloy 825 – Properties, Applications, Fabrication, Machinability and Weldability of Incoloy 825. AZoM, viewed 28 May 2022, https://www.azom.com/article.aspx?ArticleID=4245.

Very useful data and information. Thanks...

Very useful information. Thank you.

Best Metal Reference Site for Alloy Steels

The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of AZoM.com.

Do you have a review, update or anything you would like to add to this article?

In this interview, AZoM talks to Chris Aylott, Senior Engineer at Newcastle University, about fatigue testing in the development of low carbon transport solutions.

AZoM speaks with Dr. Nicola Ferralis from MIT about his research that has developed a low-cost process of creating carbon fibers from hydrocarbon pitch. This research could lead to the large-scale use of carbon fiber composites in industries that have thus far been limited.

In this interview, AZoM speaks with Marco Enger, Senior Tribologist from GGB, to discuss how nano fillers affect transfer films within tribological systems.

This product profile outlines the Versa Flex Checkweighers from Thermo Fisher Scientific.

The LQA 300 FT-IR wine analyzer combines performance, accuracy, ease-of-use, and speed for the analysis of finished wine, must and must under fermentation samples in less than 45 seconds—all in one compact solution.

The SpectraStar™ XT-R Benchtop NIR can analyze virtually any sample type in less than a minute, including solid, slurry, or liquid samples.

This article provides an end-of-life assessment of lithium-ion batteries, focusing on the recycling of an ever-growing amount of spent Li-Ion batteries in order to work toward a sustainable and circular approach to battery use and reuse.

Corrosion is the degradation of an alloy caused by its exposure to the environment. Corrosion deterioration of metallic alloys exposed to the atmosphere or other adverse conditions is prevented using a variety of techniques.

Due to the ever-increasing demand for energy, the demand for nuclear fuel has also increased, which has further created a significant increase in the requirement for post-irradiation examination (PIE) techniques.

AZoM.com - An AZoNetwork Site

Owned and operated by AZoNetwork, © 2000-2022