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Hastelloy C22 and C276 differ greatly in their applications due to their differing chemical compositions. As a matter of fact, Hastelloy C22 is of great importance due to its enhanced versatility and exceptional resistance to chloride pitting, while Hastelloy C276 is of great importance due to its proven ability to withstand a wide variety of aggressive chemicals.

This alloy is made of nickel-chromium-molybdenum, and it has a different chemical composition from that of Hastelloy C22 and Hastelloy C 276. Consequently, the alloys can be used in various applications due to their chemical compositions. It is widely known that Hastsloy C22 has a higher chromium content than Hasteloy C276, which is why it is extremely resistant to oxidising environments.

Difference Between Hastelloy C22 and C276

It is important to consider three factors when selecting a material: its property, its price, and its availability. There are many materials mentioned in the industry but few that are actually produced in the form needed for a project. Choosing the right material for our purpose is often a difficult decision.

There are times when some materials, such as Hastelloy C-22 and Hastelloy C-276, are frequently mixed up and/or welded with one another on a regular basis for a variety of reasons.

It is the name of a family of corrosion-resistant alloys known as Hastelloy. In spite of the similarity between C-22 and C-276, and the fact that both belong to the Hastelloy family, C-22 is often referred to as the upgrade from C-276 because it has better corrosion resistance than C-276.

C-22 has a higher percentage of chromium than most other materials, which means that the material will perform better in oxidising environments, extending the life of the material. The most commonly used severe oxidising media are sodium chloride (NaCl), hydrochloric acid (HCl), and sulfuric acid (H2SO4). Furthermore, C-22 exhibits excellent resistance against ferric and cupric chlorides, acetic anhydride, formic and acetic acids, hot organic and inorganic acids, brine solutions, and seawater.

What Is Hastelloy C22?

In addition to its resistance to both oxidising and non-oxidizing chemicals, Hastealloy C22 is also a nickel, chromium, and molybdenum alloy. Its principal characteristics include its resistance to oxidising and non-oxidizing chemicals. Stainless steel, for example, is susceptible to chloride-induced pitting, a form of attack that is unpredictable and can result in pitting. This protection, for example, provides a means of protecting against that attack. The material also protects against crevice attack and stress corrosion cracks.

Hastelloy C22 tubes

As a result, this alloy has a higher chromium content than other Hastelloy alloys. Aside from that, this alloy has excellent ductility and weldability. Most of the time, industrial components can easily be constructed with them. This alloy is available in sheets, strips, billets, bars, wires, pipes, and so on. Reactors, heat exchangers, and columns are among the applications of this alloy in the chemical process industry. This alloy has the following chemical composition;

  • The nickel content is 56%
  • 22% chromium
  • 13% molybdenum
  • 3% iron
  • 3% tungsten
  • 2.5% cobalt

What Is Hastelloy C276?

As with Hastelloy C22, Hastelloy C276 is primarily composed of nickel, chromium, and molybdenum, and contains a comparatively high concentration of chromium. This alloy is mainly nickel-based, with a low chromium content than Hastelloy C22. The primary importance of this alloy is the fact that it has performed well in various aggressive chemicals (for over 50 years). Furthermore, it is the first alloy in the Hastelloy family that has been tested in a wide variety of aggressive chemicals over the last 50 years.

Hastelloy C22 tubes

This alloy is ductile and welded well, like other Hastelloy alloys. The material is exceptional against stress corrosion cracking as well as corrosive chemicals such as oxidizing and non-oxidizing acids, as it contains a lot of chromium and molybdenum. As well as demonstrating outstanding resistance to pitting in the presence of chloride and other halides, it also resists stress cracking caused by sulfides. 

There are several commercial Hastelloy grades of this material, including plates, strips, sheets, billets, bars, wires, pipes, etc. Its chemical Hastelloy composition is as follows:

  • The nickel content is 57%
  • 16 % chromium
  • 16% molybdenum
  • 5% iron
  • 4% tungsten
  • 2.5% cobalt

How Do Hastelloy C22 And C276 Differ?

The Hastelloy C22 and C276 Hastelloy are both composed mainly of nickel, chromium, and molybdenum with an elevated amount of chromium. Hastelloy C22 and C276 are alloy materials made up of several metals, but the composition of each metal in the alloy makes Hastelloy C22 different from C276. Considering this difference, Hastelloy C22 and C 276 alloy have a variety of chemical industry applications. Among Hastelloy, C22 is essential because of its enhanced versatility and resistance to chloride-induced pitting, whereas C276 is key because of its proven performance in a broad range of aggressive chemicals.

Hastelloy C22 Vs C276 Price

Purchasing welding materials for C276 is easier than procuring welding materials for C22, which are easily available from one to two locations.

In general, C22 performs better than C276, but those two can be used under most conditions.

The costs of the two are similar on a material basis since they have few differences in their components. However, C22 cannot be widely produced and supplied, so the price of C22 should be lower than C276 since its density is smaller. Therefore, C22 has a higher cost because it cannot be widely produced and supplied.

Anti-Corrosion Nickel Based Alloy Hastelloy C22 Vs C276

Pitting corrosion, crevice corrosion and stress corrosion cracking are all resistant to Hastelloy alloy.

The corrosion-tolerant properties of the material were well observed when exposed to a wide range of corrosive media in both oxidation and reduction environments, up to as high as 677 °C in the laboratory; Hastelloy c-22 and c-276 are the only metals that are resistant to corrosion from a number of chemicals, such as chlorine gas, hypochlorite, and chlorine dioxide solution, and also provide excellent corrosion resistance to high concentrations of chloride solutions (like iron chloride and copper chloride).

In addition to having excellent welding characteristics, Hastelloy C-22 and C-276 are widely used in chemical and petrochemical fields, especially in applications involving chlorinated organics and catalytic systems. A seawater corrosion environment, mixed with impurities of inorganic acids and organic acids (such as formic acid and acetic acid), is a perfect environment to use them at high temperatures.

Compared to Hastelloy C-276, Hastelloy C-22 is more corrosion-resistant.

A material's ability to endure different environments determines its life—and ultimately its cost. Taking a closer look at C-22 and C-276, they have about 22% chromium and 16% chromium, respectively. However, this 6% difference results in better corrosion resistance in oxidizing environments than C-276, so the alloy can last for about 5 to 10 times longer.

C-22 And C-276 Weldability

In selecting materials, property, price, and availability must be considered. In our industry, there are many materials talked about, but few of them are produced in a product form suitable for a project. It is often difficult to choose the right material for our purpose.

It is not uncommon that parts of some of these alloys, such as Hastelloy C-22 and Hastelloy C-276, get mixed together or welded together regularly as a result of mishandling.

The Hastelloy alloy is one of a variety of corrosion-resistant alloys that belong to the Hastelloy family. It is known that C-22 and C-276 belong to the Hastelloy family. However, C-22 has a higher degree of corrosion resistance and is often referred to as the upgrade from C-276 despite the similarity.

A higher percentage of chromium in C-22 provides better corrosion resistance in oxidizing environments, increasing its life significantly. There are many severe oxidizing mediums, such as sodium chloride, hydrochloric acid (HCl), and sulfuric acid (H2SO4), that are commonly used. As well as being resistant to ferric and cupric chlorides, acetic anhydride, formic and acetic acids, hot contaminated organic and inorganic acids, brine solutions, and seawater, C-22 also exhibits outstanding corrosion resistance.

In the family of Hastelloy, Hastelloy C22 and Hastelloy C276 both belong to the same family of alloys. Due to the differences in their chemical compositions, these two alloys serve many different purposes in the chemical industry. It is important to note that Hastelloy C22 is much more important than C276 because of its exceptional versatility and its outstanding resistance to chloride pitting. One major difference between Hastelloy C22 and C276 is that Hastelloy C22 is very important due to its exceptional versatility and exceptional resistance to chloride pitting, whereas Hastelloy C276 is very important due to its proven performance in a wide range of aggressive chemicals.