Nickel element is a known material for both scientists and people due to its numerous applications in everyday life and industries. It is estimated that Nickel is mined about 2.7 million tons annually in the form of ore, and then it is purified. Also, the biggest miners are Indonesia, the Philippines, and Russia. Its application in industries is mostly because Nickel is resistant to corrosion, and this is because the Nickel slowly reacts with air and forms a thin oxidized layer. So, it will resist reacting with the corrosive materials. Although Nickel is resistant to corrosion, it is not optimized for acidic environments and also strong acids. Therefore, to maximize its resistance and also to make a more robust material, scientists have produced many alloys by combining different amounts of Nickel with certain elements including Copper, Chromium, Molybdenum, Titanium, and so on. Nickel alloys are among the favorite alloys of engineers, and this is due to the levels of Corrosion and Heat resistance that they provide, which is usually not found in other materials and alloys. For instance, Monel (created from the combination of Nickel and Copper) has a higher resistance to heat and contaminated waters. In this article, we will examine some of the most important alloys that are applied in industries.
Nickel-Copper
Nickel and Copper have similar structures as they are neighbors in the periodic table, and this has led to the creation of a strong alloy. Monel is the name of this combination which provides excellent resistance to reducing acids, specifically Hydrofluoric acid (in all temperatures and concentrations), and is also resistant against seawater. Monel is available in many types that vary in the percentage of elements used in producing them. For example, Monel K400 and K500 are two of these types, whereas K500 has more Titanium and aluminum in its structure. This addition of Titanium and Aluminum has provided K500, with the greater heat resistance from colder than 0°C to more than 450°C. It is applied in many industries with many forms, including round bars, round tubing, pipes, and flanges
Nickel-Molybdenum
It is usually called Hastelloy B, and the most important thing about this alloy is its resistance against Hydrochloric acid, Hydrobromic acid, and Sulfuric acid. Therefore, Hastelloy B has long been used in chemical industries. However, Hastelloy B cannot withstand oxidizing acids or materials that contain an oxidizing species, including Oxygen, Chlorine, Bromine, and etc. It is also resistant to stress corrosion cracking. Due to all of these great properties, Hastelloy is applied in reaction vessels and transition ducts in Oil & Gas and Pharmaceutical industries.
Nickel-Chromium
The most common types of this alloy are Inconel 600 and 625. These alloys are highly resistant to oxidative and corrosive materials. Also, Inconel is a very hard metal that can stand high temperatures. These properties make Inconel useful for the environments that steel cannot tolerate. Inconel is used in Nuclear Power Plants, Jet Engines, and expansion joints. One of the best application examples is Spacex that uses Inconel in the engine manifold.
Pure Nickel
We indeed talked a lot about Nickel alloys and their applications, but commercially pure Nickel is a very useful material itself. Nickel is used in electronic systems, especially in magnetic systems, aerospace, coating, Storage batteries such as nickel-cadmium, and so on. It is also resistant to caustic materials in all temperatures and concentrations. For example, Nickel 200 is a 99.6% pure Nickel that has good resistance to corrosive environments and has a magnetic property. It is mostly used for maintaining food, in containers of chemical materials, and so on. Also, Duranickel 301 is a Nickel-based superalloy that is produced by age hardening and strengthening of Nickel 200. Duranickel 301 has great electrical conductivity and is so strong that it is applied as springs that can pass an electrical current.
