SA283 Grade A/B/C/D steel plates are carbon steel plates. The performance of carbon steel mainly depends on the carbon content. As the carbon content increases, the strength and hardness of the steel increase, while the plasticity, toughness and weldability decrease. Compared with other steels, carbon steel is used the earliest, with low cost, wide performance range and the largest consumption. It is suitable for media such as water, steam, air, hydrogen, ammonia, nitrogen and petroleum products with a nominal pressure PN≤32.0MPa and a temperature of -30-425°C.
1. Sulfur, oxygen, and nitrogen can all increase the hot brittleness of steel, and an appropriate amount of manganese can reduce or partially offset its hot brittleness.
2. Residual elements except manganese and nickel reduce the impact toughness of steel and increase cold brittleness.
3. Except that sulfur and oxygen reduce the strength, other impurity elements increase the strength of steel to varying degrees.
4. Almost all impurity elements can reduce the plasticity and weldability of steel.
Hydrogen can cause many serious defects in steel, such as white spots, point segregation, hydrogen embrittlement, surface bubbling, and cracks in the heat-affected zone of the weld. In order to ensure the quality of steel, the hydrogen content in steel must be reduced as much as possible. Residual elements brought in by deoxidation, such as aluminum, can reduce the aging tendency of low-carbon steel, and can also refine grains and improve the toughness of steel at low temperatures, but the balance should not be too much.
