Q345B angle steel and Q355B low alloy angle steel are two kinds of steel commonly used in steel structure engineering, and their basic overview is as follows:
First, the material and performance characteristics.
Q345B angle steel and Q355B low-alloy angle steel are both low-alloy high-strength structural steels, which have excellent properties such as high strength, high toughness, fatigue resistance and impact resistance. Among them, the yield strength of Q345B angle steel is 345MPa, the tensile strength is 500-700MPa, and the elongation after fracture is 18%.The yield strength of Q355B low-alloy angle steel is 355MPa, the tensile strength is 470-630MPa, and the elongation after fracture is 18%. The chemical composition and mechanical properties of these two types of angle steels are in line with the provisions of the national standard GB T 11263-2017 "hot-rolled H-beam and split T-beam".
2. Types and uses.
Q345B angle steel and Q355B low-alloy angle steel can be divided into two kinds of equal angle steel and unequal angle steel according to the cross-sectional shape. Among them, the two sides of the equilateral angle steel are equal, and the common specifications are 25mm 25mm, 30mm 30mm, 40mm 40mm, 50mm 50mm, etc.;Unequal angle steel has different lengths on both sides, and the common specifications are 25mm 100mm, 25mm 120mm, 30mm 80mm, 40mm 70mm, etc.
Q345B angle steel and Q355B low alloy angle steel are mainly used in steel structure construction projects, such as workshops, warehouses, high-rise buildings, bridges, railways and other fields. As the main support and connection materials, they have the advantages of high strength, good stability and easy installation, which can significantly improve the bearing capacity and seismic performance of buildings. At the same time, these two kinds of angle steel can also be processed into various shapes and sizes of components according to needs to meet the needs of different projects.
Third, the production process and market conditions.
The production process of Q345B angle steel and Q355B low-alloy angle steel mainly includes smelting, continuous casting, rolling and other links. In the production process, in order to ensure the quality and performance of steel, strict quality control and testing are required, such as chemical composition analysis, mechanical property testing, metallographic structure testing, etc. At present, there are many manufacturers of Q345B angle steel and Q355B low-alloy angle steel in the domestic market, and the market competition is fierce. With the rapid development of the construction industry, the demand for these two types of angle steel is gradually increasing.