Introduction
20MnTiB alloy structural steel is a new type of alloy structural steel developed according to the development needs of the steel structure industry. It is a low-temperature alloy quenched and tempered steel. 20MnTiB alloy structural steel has excellent mechanical properties and workability, as well as good weldability, good quality and weldability, and good plastic deformation properties. At the same time, it also has good comprehensive performance such as toughness and fatigue resistance.
20MnTiB alloy structural steel is mainly used in the mechanical structures of automobiles, ships, locomotives and other machinery. It is also widely used in bridges, offshore oil platforms, construction machinery, Offshore engineering and other fields.
Composition
20MnTiB alloy structural steel is mainly composed of the alloy components 20Mn, Ti and B, and the mass fraction composition of the alloy components is 0.18-0.22% of C, 0.20-0.35% of Si, 0.90-1.20% of Mn, 0.08-0.15% of Ti, 0.0002-0.0050% of B, 0.015-0.035% of S and 0.0005-0.0020% of P. The mass fraction of other alloy components such as Al, V and Cr is lower than 0.050%.
Mechanical performance
20MnTiB alloy structural steel has excellent mechanical properties and workability, good weldability and plastic deformation. Its tensile strength is between 900-1120MPa, yield strength is between 780-950MPa, elongation is between 6-10%, and hardness is between 200-250HB.
Processing
20MnTiB alloy structural steel is suitable for hot and cold forming. When forging, the working temperature should not be lower than 1150℃, and during the hot working and hot extrusion process, the forging temperature should not be lower than 900℃. When cold forming, the working temperature should not exceed 425℃.
Heat treatment
The heat treatment process of 20MnTiB alloy structural steel includes annealing and quenching + tempering processes. The heat treatment process is carried out on the basis of the normalizing process. The annealing process is carried out at 850℃ and then at room temperature. In the quenching + tempering process, the quenching temperature should be 780-830℃, and the tempering temperature should be 370-420℃.
Application
20MnTiB alloy structural steel is mainly used in the mechanical structures of automobiles, ships, locomotives and other machinery, as well as in bridges, offshore oil platforms, construction machinery, offshore engineering and other fields.
Conclusion
20MnTiB alloy structural steel is a new type of alloy steel developed according to the development needs of the steel structure industry. It has excellent mechanical properties and processability, as well as good weldability and plasticity. It is widely used in the mechanical structure of automobiles, ships, locomotives and other machinery, and also has a wide range of applications in bridges, offshore oil platforms, construction machinery and offshore engineering.
