What Is Manganese?
Manganese (Mn) is a chemical element with atomic number 25 and a transitional metal of Group 7 (VIIb) in the periodic table that was recognized by Carl Wilhelm Scheele, a Swedish chemist in 1774. It is not found as a free element but in minerals in combination with iron. It has a melting point of 1246 degrees Celsius (2 274.8 degrees Fahrenheit) and a boiling point of 2061 degrees celsius (3,741.8 degrees Fahrenheit).
In its pure form, it is hard, brittle, and breakable. It cannot be worked on when it is pure, but it is an essential compound in the steel industry that is used to deoxidize steel and desulfurize. It is used in making manganese steel.
What Is Manganese Steel?
Manganese steel, also known as mangalloy or Hadfield steel, is a form of steel alloy containing 10 to 15 percent of manganese. It is a type of non-magnetic steel that is known for its extreme anti-wear properties. It is very resistant to abrasion and achieves up to 3 times surface hardness during impact without an increase in brittleness.
Most steels contain less than one percent of manganese. An increase in the manganese in steel increases both hardness and ductility. Steel with 1.5 to 4.5 percent manganese content is brittle. At 5% manganese content, the steel is not brittle, but will still smash at the strike of a hammer. At 12% manganese content, both hardness and ductility are at their highest points.
Mangalloy has a high yield and tensile strength of about 350 to 900 megapascals (MPa) that keeps increasing as its work hardens. Alloys that have a manganese content higher than 12 percent can resist the brittle effects of cold to temperatures in the range of −127 degrees Celsius (−196 degrees Fahrenheit). The material can also crumble if hammered when red-hot.
Manganese steel is the best material making rock crushers, cement mixers, and other products that require a wear-resistant material. Here are some of the things about manganese steel that you need to know.
What Is Manganese Steel Used For?
The steel industry uses manganese in deoxidizing and desulfurizing additives and alloying constituents. It helps improve stiffness, toughness, wear-resistance, hardness, and hardenability of steel as well as the rolling and forging qualities.
Steel that contains eight to fourteen percent of manganese can have a high tensile of up to 863 megapascals (MPa). Steel with more than twelve percent of manganese is used in applications that require great toughness and wear resistance.
Manganese steel is often used for manufacturing rock crushers, crawler trends for tractors, cement mixtures, elevator, and steel bucket. The rail industry uses manganese steel for producing switches, crossings, and other high impact areas. Recently, some states are using it in window bars in prisons, bulletproof cabinets, anti-drill plates, and safes.
Is Manganese Steel Magnetic?
Manganese steel or Hadfield steel is highly non-magnetics. Its non-magnetic property makes it suitable for lifting magnets in industries and manufacturing electric transformer assemblies.
Does Manganese Steel Rust?
Steel and low alloy are known to form steel rust in a moist environment. But that is not the case with manganese steel. Adding manganese to steel has a positive impact on corrosion due to the absorption of manganese ions. Manganese steel can resist corrosion.
How to Cut Manganese Steel
The difficulty in machining manganese steel restricts some of its uses. Manganese steel has a zero machinability. The higher the percentage of manganese in mangalloy, the much harder it is to cut it. You can soften manganese steel by annealing. It also hardens rapidly under grinding and cutting tools.
You need special tooling to machine manganese steel. You can drill it using diamond or carbide, but with extreme difficulty. A128 manganese steel is tougher than common carbon steel even when heated. The best way of cutting manganese steel is by using plasma or laser cutting. You can also be able to cut it with an oxy-acetylene torch.
Welding Manganese Steel
Manganese steel can be welded, but you should keep the heat low and cool the weld as soon as possible to avoid cracking.
An interpass temperature of below 260 degrees Celsius or 500 degrees Fahrenheit is the best for welding manganese steel. You should also remember to wear your protective gear when working with manganese steel because of the toxic nature of the fumes.
What Are the Benefits of Manganese as an Alloying Element
Manganese helps improve the mechanical properties of steel. It also increases the hardenability of steel by reducing the critical cooling during hardening. The effect of manganese on hardening is higher than that of other alloying elements.
To achieve materials with the best properties, manufacturers use both carbon and manganese elements together. Some carbon steels have up to 1.5 percent of manganese alloy. In the carburizing process, manganese helps boost the rate of carbon penetration, which helps make the product stronger.