What are the grades of Hastelloy C?

What are the grades of Hastelloy C?

If you are looking for a material that has excellent corrosion resistance and can withstand harsh environments such as nuclear radiation, Hastelloy is an important alloy to consider. This article will provide a detailed introduction to the meaning, characteristics, manufacturing process, and applications of Hastelloy.

What is Hastelloy material?
As the name suggests, Hastelloy is an alloy similar to steel. More specifically, it is a nickel-based alloy. Nickel is alloyed with molybdenum and chromium to form Hastelloy.

Hastelloy is further divided into different grades based on the content of molybdenum and chromium. One of the most popular grades of Hastelloy is C276.

Some of the main properties of Hastelloy include:

Corrosion resistance: Steel has limited corrosion resistance, while Hastelloy has excellent corrosion resistance. This material can even withstand acidic and corrosive chemicals. In addition, it is resistant to pitting, crevice corrosion, and stress corrosion.
Processing performance: Hastelloy is easy to form or process, and can be processed by a variety of processes such as welding and machining.
High temperature resistance: Hastelloy is resistant to high temperatures, so it can be used in harsh environments such as aerospace, chemical, and oil and gas.
Magnetic Permeability: Hastelloy alloy is known for being non-magnetic. This property is very advantageous in certain applications.

Hastelloy properties

Here are some of the important properties of Hastelloy.

How is Hastelloy made?
Hastelloy is usually made using the following methods. The manufacturing methods may vary depending on the manufacturer, grade, technology used, etc. But the following are the commonly used methods.

Selecting raw materials: The first step is to select high-quality raw materials. As mentioned earlier, Hastelloy mainly contains nickel, chromium, and molybdenum. Generally, these raw materials contain chromium content of 1% to 25% and molybdenum content of 5% to 30%. It may or may not contain iron. In addition, depending on the grade, other materials such as carbon, tungsten, vanadium, titanium, etc. can also be used to make Hastelloy.
Melting: After the raw materials are collected, they are placed in a furnace to melt. Depending on the manufacturer, electric arc furnaces or vacuum induction furnaces are usually used.
Casting: Like cast steel, Hastelloy also needs to be cast. When the materials are melted and fully combined, the next step is casting. Depending on the requirements, the molten Hastelloy can be cast into billets, bars, plates, or any other shapes.
Heat treatment: Hastelloy needs to be heat treated according to the requirements to improve the mechanical properties of the metal.
Other Processing: Manufacturing Hastelloy may also involve other processing such as annealing, surface treatment, cutting and machining, etc.
Testing and Inspection: The final step in Hastelloy manufacturing is testing and inspecting the product to see if it meets all the required standards.

Hastelloy C276: Chemical Composition
Hastelloy C276 alloy is also known as UNS N10276. The chemical composition of C276 includes nickel, chromium, and molybdenum. Hence, it has excellent resistance to chloride stress cracking and pitting corrosion. This excellent corrosion resistance is mainly due to its high content of chromium and molybdenum.

One of the most important properties of C276 grade is its radiation resistance. Hence, it is used in nuclear applications.

Applications of Hastelloy
Following are some of the common applications of Hastelloy.

Chemical/Petrochemical Processing:
Hastelloy is widely used in the chemical industry due to its ability to withstand a wide range of chemicals and chemical processing. It is often used to handle corrosive acids, strong oxidizers, and aggressive chemicals. Hence, it is commonly used to handle sulfuric acid, acetic acid, and hydrochloric acid. Moreover, it is used in reactors, heat exchangers, and piping systems. Moreover, it is also used in the agrochemical industry for handling agrochemicals and pesticides.

Oil and Gas Industry
Hastelloy is commonly used in both offshore and onshore applications. It is also widely used in natural gas exploration and production due to its resistance to sour gases and corrosive environments.

Pharmaceutical Industry
This is another industry that requires corrosion-resistant materials. Like stainless steel, Hastelloy is also widely used in the pharmaceutical industry. It is mainly used in the manufacturing of various equipment such as reaction vessels and storage tanks, where high purity and corrosion resistance are essential.

Aerospace
Hastelloy is able to withstand high temperatures and harsh environments. Therefore, it is often used in the manufacturing of aerospace components such as engine parts.

Marine Industry and Desalination Plants
Since Hastelloy does not corrode in salt water, it is an important material for marine industries and desalination plants.

Other Applications
Other industries that use Hastelloy include:

Power Generation Industry – for Flue Gas Desulfurization (FGD) systems, heat exchangers, and other components

Pollution Control Industry – for scrubbers that neutralize acidic gases

Food and Beverage Processing Industry – for equipment that needs to withstand highly acidic or corrosive cleaning solutions

Electronics Industry – for manufacturing components