Incoloy 825

Because Incoloy 825 alloy is rich in Cr, Mo, Cu, it has good general corrosion resistance to oxidizing acid and non-oxidizing acid. Especially it has extremely high corrosion resistance to sulfuric acid. Due to the high content of Cr, Mo and Ni, it has excellent pitting corrosion resistance, crevice corrosion resistance, and stress corrosion cracking resistance in a chloride environment. Incoloy 825 alloy controls the carbon content at an extremely low level, is not easy to be sensitized during welding, and has low intergranular corrosion sensitivity.

The following table shows the chemical composition of Incoloy(r) alloy 825

ElementContent (%)
Nickel, Ni38-46
Iron, Fe22
Chromium, Cr19.5-23.5
Molybdenum, Mo2.50-3.50
Copper, Cu1.50-3.0
Manganese, Mn1
Titanium, Ti0.60-1.20
Silicon, Si0.50
Aluminum, Al0.20
Carbon, C0.050
Sulfur, S0.030

Physical Properties

The physical properties of Incoloy(r) alloy 825 are given in the following table.

PropertiesMetricImperial
Density8.14 g/cm³0.294 lb/in³
Melting point1385°C2525°F

Mechanical Properties

The mechanical properties of Incoloy(r) alloy 825 are highlighted in the following table.

PropertiesMetricImperial
Tensile strength (annealed)690 MPa100000 psi
Yield strength (annealed)310 MPa45000 psi
Elongation at break (annealed prior to test)45%45%

Thermal Properties

PropertiesMetricImperial
Thermal expansion co-efficient (at 20-100°C/68-212°F)14 µm/m°C7.78 µin/in°F
Thermal conductivity11.1 W/mK77 BTU in/hr.ft².°F

Incoloy 825 alloy has the following characteristics:
1. Good resistance to stress corrosion cracking
2. Good resistance to pitting and crevice corrosion
3. Very good oxidation resistance and non-oxidizing thermal acid performance
4. It has good mechanical properties at room temperature and high temperature up to 550℃
5. Certification for pressure vessels with a manufacturing temperature of 450°C

Corrosion resistance of Incoloy 825 alloy:
Alloy 825 is a general engineering alloy. It has acid and alkali metal corrosion resistance in both oxidation and reduction environments. The high nickel content makes the alloy has effective resistance to stress corrosion cracking. It has good corrosion resistance in various media, such as sulfuric acid, phosphoric acid, nitric acid and organic acids, and alkali metals such as sodium hydroxide, potassium hydroxide and hydrochloric acid solutions. The higher comprehensive performance of 825 alloy is manifested in nuclear combustion dissolvers with various corrosive media, such as sulfuric acid, nitric acid and sodium hydroxide, which are all processed in the same equipment.

Incoloy 825 alloy application range application areas are:

Alloy 825 is widely used in various industrial fields where the operating temperature does not exceed 550°C.
Application fields of Incoloy 825 alloy:

Heating pipes, containers, baskets and chains used in sulfuric acid pickling plants, sea water cooling heat exchangers, marine product piping systems, acid gas environment pipes, heat exchangers, evaporators, washing, immersion pipes, etc. in phosphoric acid production, petroleum Refining air heat exchangers. Food engineering chemical processes, flame retardant alloys for high-pressure oxygen applications.
For metal material problems, look for Shenzhen Huani Special Alloys. Hua Nickel focuses on solving the metal material problems of user products in the comprehensive and complex working environment such as high temperature, high corrosion, high creep, high strength, high hardness, high wear resistance and high temperature corrosion resistance capillary tubings.

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