Which of the following is not considered a structural steel?

Tool and die steel is typically not classified as structural steel. Structural steels are primarily designed to support loads and stresses in construction and architectural applications. They have specific grades and properties that make them suitable for structural applications, including good weldability and ductility.

In contrast, tool and die steel is specifically engineered for making tools and dies due to its high hardness, wear resistance, and ability to retain shape under high stress and temperature. These characteristics make tool and die steel ideal for cutting tools, molds, and other applications where precision and durability are essential, but do not align with the requirements for structural integrity in construction.

On the other hand, stainless steel, medium carbon steel, and low carbon steel are commonly used in structural applications. Stainless steel provides corrosion resistance along with strength, medium carbon steel offers a good balance of strength and ductility, while low carbon steel is often used for its high malleability and good weldability, making all three suitable for structural integrity in various engineering designs.