Heat treatment analysis of SM570 steel

SM570 steel is a grade of low-alloy high-strength steel plate, and its strength and grade are the highest in the Japanese standard JIS G3106. It is widely used in construction machinery, bridges, containers, vehicles, power equipment and other structural parts. SM570 low-alloy high-strength sheet has high strength and low-temperature impact toughness. It has long been used in major engineering machinery factories and coal mine machinery factories.
 

Heat treatment analysis of SM570 steel plate:

a. The SM570 yield strength is 460MPa. Because this strength grade steel contains a variety of alloying elements, including microalloying elements, it can often reach higher strength under hot rolling or controlled rolling, but the impact toughness fluctuates greatly. , The performance is not stable, it is obvious that the hot rolling process, especially the final rolling temperature and cooling rate, have a huge impact on the performance.
b. For extra-thick plates, the adaptability of controlled rolling is even more restricted, and it is more difficult to balance strength and toughness. The normalizing has the advantages of uniform and stable steel structure and performance, high qualification rate, and easy control of the production process.
c. For users, in some places where hot forming or final heat treatment is required for the structure, it is also very advantageous to use normalized steel, because it will not be like hot-rolled or controlled-rolled steel sheets after hot forming or heat treatment. That is, the intensity is greatly reduced. For this reason, American, German and European standards all stipulate that this strength grade steel should be delivered by normalizing, such as ASTM A633/A633M, DIN17102, EN10113, EN10028