Q345 Steel (GB/T 1591) | Equivalent Materials and Metal Specifications

Q345 Overview

Q345 is a low alloy steel material commonly used in motor vehicles, bridges, ships, and construction. Also known as GB/T 1591, the Q signifies the yield point, and 345 references the strength of yield. It is essential to note that the yield value decreases as the material thickness increases.

Q345 Equivalent Materials

Q345 can also be replaced with equivalent materials, including A572 Grade 50 (USA ASTM), Q355 (China GB/T), and SPFC 590 (Vietnam/Japanese JIS).

Characteristics of Q345

The yield strength of Q345 is where the material begins to deform plastically. Before hitting deformation, it will return to its original shape when stress is removed. For Q345, the yield strength is 345 MPa.

Like many in its grade, Q345 will endure elongation before pulling apart, which typically occurs at 20 percent of its initial length. Q345 has a tensile strength rating of 470 to 660 MPa, which means it can handle heavy-duty stress and use before ever failing.

Q345 steel is from the 16 Mn steel grade, typically manufactured in a hot rolled steel coil or sheet or a hot rolled steel plate. It is an excellent choice when you need high-pressure durability. The welding properties are primarily affected by the chemical content, and production technology has significantly improved after years of research, making it an excellent steel standard for structural purposes.

Uses of Q345

Q345 has excellent mechanical properties, good performance in low temperatures, and excellent weldability and plasticity. It is most commonly used in building structures, low-pressure vessels, cranes, mechanical parts, bridges, ships, petroleum storage tanks, lifting machinery, power stations, mining machinery, general metal parts, and in other structures exposed to temperatures of -40 C or below or experiencing high loads.

Q345 Physical Properties

Q345 Mechanical Properties

Q345 Chemical Composition