Austenitic SS Sanrico 28

Austenitic SS Sanrico 28

Sanrico 28 or UNS N08028 is a nickel-chromium iron-based alloy as its main elements belong to the groups of austenitic stainless steel and are highly resistant to various corrosion environments. Sanrico 28 is also referred to as Superalloy Incoloy 28.

Incoloy 28 or UNS N08028 alloys are made with nickel, chromium, and iron as the main elements. Additions of molybdenum, copper and nitrogen give this alloy strength and corrosion resistance.

Chemical composition of Incoloy alloy 28

GRADE Cr Ni Mo Mn Si P Cu S C Cu Fe
ALLOY 28 Min 26 30 3 1 0.75
Max 28 32 4 2 0.7 0.03 2 0.01 0.02 1.5 BALANCE

UNS N08028 alloy is stainless steel formulated for initial forming into wrought products. It has a medium to high base cost in wrought super austenitic stainless steel. Along with it, it has a normal to high ductility and a medium quantity of high embodied energy. 

Corrosion resistance

Incoloy 28 or UNS N08028 along with molybdenum, copper, and nitrogen make it stronger, and corrosion-resistant. These alloys are into the superalloys category as they have high strength and the ability to function at elevated temperatures. 


ALLOY 28 N08028 NO NAME 2584 Z1NCDU31-27-03
1.4563 X1NiCrMoCuN25-20-5

UNS N08028 or Incoloy 28 alloy is a part of the austenitic stainless steel group with its resistance to a bunch of corrosive conditions. The combination of chromium and molybdenum are the reasons why this alloy is resistant to both oxidizing and reducing acids and salts. Incoloy alloy 28 is resistant to sulphuric acid because of its copper content.

Physical Properties

Grade Density (g/cm3) Thermal Conductivity (W/m.K) Specific Heat (J/Kg.K) Electrical Resistivity (Ωmm2/m)
ALLOY 28 8 at 100°C 0-100°C at 20°C
12 450 1

Sanicro 28 which is an alternative name to the Incoloy 28 is a multipurpose stainless steel alloy are characterized by better corrosion resistance in various environments like those with strong acids and conditions that are stressful. 

Alloy 28 or sanrico28 has an entirely austenitic structure due to its very high nickel content. The alloy is sensitive to intermetallic phase precipitation when the heat is treated between 700 and 1100°C (1292 and 2012°F). 

Applications of Sanicro 28

Alloy 28 or Sanicro 28 was primarily developed to overcome the wet-process phosphoric acid heat exchanger material. The corrosion resistance properties to enable it to H2S, phosphoric acid, chloride, and sulfuric acid corrosion resistance which is used on a large scale in H2S content in the oil and gas fields, flue gas desulfurization system, seawater and chloride-bearing cooling water, and paper industry. 

The Incoloy 28 alloy is widely used in phosphoric acid applications and some sulphuric solutions. Alloy 28 is also being used in caustic solutions as its molybdenum content remains low when compared to the nickel and chromium additions.

The high contents of nickel and molybdenum are the reasons why Alloy 28 has an excellent resistance to stress corrosion cracking conditions. Especially they are used for high-temperature applications (140°C – 400°C to 284°F – 752°F) and chloride containing environments. Alloy 28 is designed for sour gas applications and has been well-tried and tested at 230°C (446°F).

Superalloy Incoloy 28 is particularly resistant to sulphuric and phosphoric acid and is used for pollution control equipment, chemical processing, oil and gas well piping, nuclear fuel reprocessing, pickling equipment, and acid production.