Nickel Alloy: What is Hastelloy C22?
Nickel alloys are getting more and more recognition in the market. This is due to the fact that nickel alloys have several industrial applications. In this blog, we will take a look what Hastelloy C22 is and its industrial applications. We will also take a look at the chemical properties of Hastelloy C22. Read on to learn more about Hastelloy C22 here:
What is Hastelloy C22?
Hastelloy C22 is also known as Alloy C22. It is one of the most versatile and authentic alloy of nickel. Hastelloy C22 is an alloy made by mixing nickel, chromium, molybdenum, and tungsten. It has corrosion resistance compared to other alloys made from nickel, chromium, and molybdenum. It has corrosion resistance properties than alloys like C 276, alloy C4, and alloy 625.
The high chromium content in hastelloy C22 provides good resistance to oxidization. On the other hand, it has molybdenum and tungsten, which gives it a good resistance to reducing media. Due to this corrosion resistance properties, Alloy C22 is very useful in applications where strong acids are present.
Chemical composition of Hastelloy C22
Hastelloy C22 is a nickel-chromium-molybdenum alloy. It is a superalloy that contains 56% nickel, 22% chromium, and 13% molybdenum. It also contains iron, tungsten, and cobalt. This alloy is commonly known as Hastelloy C22. However, it is also known as UNS N06022. C22 has good corrosion and oxidation resistance. It also has a good mechanical properties over a wide range of temperatures. This alloy also has good fabrication properties.
Characteristics of Hastelloy C22
1. Corrosion Resistance
Hastelloy C22 is one of the most corrosion resistant alloys in the market. It is even considered better than C276 and C625. This alloy of nickel is resistant to almost all reducing and oxidizing environments. These harsh environments feature strong oxidizers, seawater, and several organic acids. In addition to this, it also has good resistance to chloride-induced localized corrosion. Because of this corrosion resistance property, this nickel alloy has several applications.
2. Oxidation Resistance
C22 has great resistance to oxidation, carburization, and sulfidation at high temperatures. However, it is not ideal to use C22 at temperatures above 1250°F. This is due to the possible formation of embrittling phases. Due to this oxidation resistance property, C 22 has great applications.
3. Mechanical Properties
Hastelloy C22 is typically used in the annealed condition which features a minimum yield strength. This alloy can be cold worked to higher strength levels. The melting point of C22 is 1399 °C.
4. Heat Treatment
Hastelloy C22 is usually annealed at 1121°C. It is then followed by rapid cooling. It’s melting point is 2550 °F. Due to this, alloy C22 has several applications.
Hastelloy C22 alloy can be cold worked and hot worked both. C22 hardens rapidly for work process. Cold working must be performed on this alloy in stages with intervening anneals. Parts of this alloy should be annealed after cold working.
Applications of Hastelloy C22
Due to its impressive corrosion resistance property, C22 is used in various markets where harsh environments are present. This includes chemical processing, pharmaceuticals, power generation, food processing, oil & gas, and even the paper industry. Following are the applications of Hastelloy C22:
- Chemical Processing
- Oil & Gas
- Food Processing
- Power Generation
- Pharmaceutical Industry
- Pulp and Paper Industry
- Nuclear fuel regeneration
- Pesticide manufacturing
- Acid cleaning system
- Sulfur dioxide cooling tower
Fabrication and Heat Treatment
Due to the fact that C22 has good density, it is easy to hot forge, hot roll, and hot upset. It can the be followed by heat treatment. The temperature range for hot working is quite narrow. The start temperature which has been recommended for hot forging C22 is 1232°C. And the recommended finish temperature is 954°C.