Non-ferrous material

Non-ferrous materials are a small part of the total piping materials, and they are used in a very aggressive environment. Non-ferrous material contains no iron or in a very insignificant amount.

These materials are more expensive than ferrous metals. Some of the non-ferrous material used in Process Industries are listed below. The non-ferrous materials are also known as exotic material.

  • Copper and Copper Alloys
  • Nickel and Nickel Alloys
  • Aluminum and Aluminum Alloys
  • Titanium and Titanium Alloys
  • And Zirconium and Zirconium Alloys

 Copper and Copper Alloys

  • Good thermal conductivity and good corrosion resistance
  • Brasses, Bronzes (Cu-Sn) and Cupronickels (Cu-Ni) are some of the examples of the copper alloy
  • Cupronickels have the highest corrosion resistance among Cu alloys
  • Cupronickels are used for heat exchanger tubing and seawater application
  • It can be used as a cladding material with carbon steel in heat exchanger tube sheets.
Cupronickels elbow

 Nickel and Nickel Alloys

  • Good resistance to oxidation and corrosion
  • Monel 400 and Hastelloy are a well-known example of nickel alloys
  • These alloys are used in piping systems, pressure vessel, turbine blades, valves, and power plant accessories that handle steam at very high pressure and temperature
  • Nickel alloys are frequently used as a cladding material with carbon steel

 Aluminum and Aluminum Alloys

  • Good thermal conductivity
  • It is most workable metal
  • Highly resistant to atmospheric conditions
  • But When coupled with more noble materials it is subject to galvanic attack
  • And Loses strength rapidly above 175°C
  • Aluminum and Aluminum Alloys rarely used in process piping
  • However, it is used as an external cladding material to protect the insulation from water ingress.
Piping Courses
aluminium cladding for pipe

Image – Geo Thermal

 Titanium and Titanium Alloys

  • High strength to weight ratio
  • Similar to SS, Titanium Oxide is formed on the surface which prevents corrosion
  • Titanium and Titanium Alloys has resistant to nitric acid, which is very corrosive in nature. Hence, it is used in this kind of process environments.
  • However, to Weld Titanium and Titanium Alloys, the inert atmosphere is required.
  • It starts losing its strength above 400°C
  • Titanium is also used as a clade material with carbon steel to reduce the cost of equipment

Zirconium and Zirconium Alloys

  • Zirconium and Zirconium Alloys are used, where strong acids and alkalis are present, where other materials cannot be used due to the very aggressive environment.