Low-alloy high-strength steel is a kind of engineering structural steel shaped by adding a small amount of Mn, Si and trace amounts of alloy elements such as Nb, V, Ti and Al to carbon structural steel.
The so-called low alloy means that the total amount of alloying elements in the steel does not exceed 3%. High strength is relative to carbon for engineering structures use.
This type of alloy steel is mainly used for manufacturing a variety of engineering structures that require higher strength, such as bridges, ships, vehicles, high pressure vessels, oil and gas pipelines, and large steel structures.
Since such alloy steels do not require complicated treatment processes and even do not perform heat treatment, they can obtain higher strengths and greatly reduce the quality of the engineering structure. Therefore, such steels are used to replace the general carbon structural steels.