Low alloy steel is a type of steel that has other materials added to it, but the other materials typically make up a small amount of the entire steel. Steel commonly is an alloy consisting of carbon and iron, but low alloy steel often adds hard metals such as nickel and chromium. This steel usually is hard and difficult to weld, but the steel’s characteristics can be changed depending on the inclusions. This most commonly is used to make large pipes for the oil industry, but it also can be used for construction and military purposes.
Steel itself is a very basic alloy that uses a mixture of iron and carbon. In low alloy steel, iron and carbon still are used in the alloy mixture, but other materials also can be added. The materials commonly are metals and typically are very hard or tough, but they do not have to be. Non-metal materials, such as silicon, sometimes are used in this steel.
One advantage of this type of steel is that metallurgists are able to change the steel’s characteristics. While there are many materials that can add a wide range of new characteristics to steel, metallurgists cannot add them all to this steel. Low alloy-type steel can, from a technical standpoint, only have from 1 percent to 5 percent of another material added to it. If more is added, then it is considered a different type of material and may begin to lose the desirable elements inherent to steel.
Most low alloy steel is made to be very tough and hard, which helps it withstand a high amount of punishment. At the same time, this can make it difficult to use for welding, because most steels made through this process are tough to bend and work with. If softer or more weld-friendly materials are used, then this disadvantage is mitigated, even though that often decreases the extra hardness and toughness.
Its commonly increased hardness and toughness means low alloy steel most often is found in large piping systems used by the oil industry. Depending on what materials are used in the alloy, this steel also can be made suitable for construction, ship building, military vehicles and pressure vessels. Each alloy presents different characteristics, so these qualities should be checked before using this steel for any purpose. For example, if a steel with poor corrosion resistance is used for piping, then the pipes may quickly wear away.