What is the factors to influence the materials of warehouse?

The materials of steel structure workshop is steel , the followings factors influence the specification of the materials.

1, Chemical composition steel of steel structure workshop
1.1, Carbon: The main component of the steel strength. The  more carbon content , the more strength of the steel , but the less plasticity, resistance, cold bending function, weldability and rust resistance , especially the impact resistance at low temperatures is also lowered.
1.2, Manganese and Silicon: The beneficial elements in steel are deoxidizers that increase strength without excessively reducing plasticity and impact resistance.
1.3, Vanadium, niobium and titanium: alloying elements in steel can not only improve the strength of steel, but also maintain outstanding plasticity and durability.
1.4, Aluminum: Strong deoxidizer, which uses aluminum to make up for deoxidation, which can further reduce harmful oxides in steel.
1.5, Chromium and nickel: alloying elements that improve the strength of steel.
1.6, Sulfur and phosphorus: impurities and harmful elements left in steel during exercise. They reduce the plasticity, resistance, weldability and fatigue strength of steel. Sulfur can make steel "hot brittle", and phosphorus makes steel "cold and brittle".
1.7, "Hot-brittle": Sulfur can form iron sulfide which is easy to melt. When the temperature is 800-1000 °C by hot working and welding, the steel appears to be cracked and brittle.
1.8, "Cold and brittle": At low temperatures, phosphorus makes the impact resistance of steel significantly reduced.

2, Metallurgical process
Common metallurgical defects such as segregation, non-metallic doping, pores, cracks, delamination, etc., will make the steel function worse.

3, Steel hardening
Cold drawing, cold bending, punching, mechanical shearing and other cold working causeslarge plastic deformation,  the steel yield point is improved, reduces the plasticity and resistance of the steel. This phenomenon is called cold work hardening or strain hardening.

4, Temperature influence
Steel is sensitive to temperature, and both temperature rise and fall cause the steel function to change. the low temperature function of steel is more important.
At the positive temperature scale, temperature rises, the strength of the steel decreases and the deformation increases. The steel function does not change much within about 200 ° C. The strength (strength and tensile strength) drops sharply between 430 and 540 ° C; the strength is very low at 600 ° C . In addition, there is a blue-brittle appearance near 250 °C, and there is a creeping appearance at about 260-320 °C.