In order to easily and economically perform hot or cold processing to make various parts of engineering structures, the low alloy high strength steel must have appropriate forming properties. Like A572 grade 60 high strength steel, carbon structural steel, low alloy high strength steel can generally be processed in such way, as well as cutting, punching, and machining. Although the yield point of low alloy high strength steel is high, even if the forming operation is deformed quite severely, cold bending presses, drawing machines, presses and other equipment used for carbon structural steel forming can also be used for low alloy high strength steel, but some equipment needs to be modified.
The addition of Ca element in steel such as A572 grade 60 high strength steel can refine grain size, partly desulphurize and change the composition, quantity and morphology of non-metallic inclusions. It is similar to that of adding rare earth in steel. It can improve the corrosion resistance, wear resistance, high temperature and low temperature resistance of steel, improve the impact toughness, fatigue strength, plasticity and welding performance of the steel, and increase the cold heading, shock resistance, hardness and contact endurance strength of the steel.
In the whole steel structure and steel body, the medium and heavy plate is an important part, once the problem occurs, it is easy to fracture, collapse and occur explosion. So how to judge whether the medium and heavy plate, A572 grade 60 high strength steel is of high quality? First of all, check whether there are cracks on the surface of the A572 grade 60 high strength steel plate and how glossy it is. Secondly, to measure the thickness error of medium and heavy plate, it is better to use the instrument to measure the bending tensile value. Finally, observe the scale of the steel plate manufacturers, whether there are relevant qualification certificates, and how the production process is.
In addition, according to customs statistics, from January to February, 7.81 million tons of A572 grade 60 high strength steel and so on steel were exported, 2.04 million tons of imported steel, and 6.01 million tons of net exported steel were converted into crude steel, a year-on-year decrease of 33.7%. According to the above data, the average daily supply of crude steel in China from January to February was 2478200 tons, down 5.09% from December of last year, up 3.70% year on year. Compared with the situation of delayed demand, steel production keeps growing, and the market presents a situation of supply exceeding demand.
