Quenching and tempering (QT) is a double heat treatment process of quenching and high temperature tempering. In general, medium carbon steel and medium SA633 Gr A high-strength structural steel carbon alloy steel often need quenching and tempering treatment. Quenching and tempering can make iron and steel parts obtain a good combination of strength and toughness, with high strength, excellent toughness, plasticity, cutting performance, etc. Some SA633 Gr A high-strength structural steel alloy steel or low alloy steel must be quenched and tempered to obtain good comprehensive properties. These steels can also be called quenched and tempered steels.
As steel transportation belongs to the transportation of major parts, so in the process of transportation, modern logistics technology, such as centralized transportation, information technology, is a bit out of place. Based on the current situation of China's SA633 Gr A high-strength structural steel steel transportation industry, highway transportation is a way of transportation that many enterprises often choose. Naturally, its business volume also accounts for more than 50% of the whole SA633 Gr A high-strength structural steel steel transportation industry.
The use of low carbon steel is limited due to its low strength. The strength of the carbon steel can be greatly improved by properly increasing the manganese content in the SA633 Gr A high-strength structural steel carbon steel and adding some alloy elements such as vanadium, titanium and niobium. If the carbon content in the carbon steel is reduced and a small amount of aluminum, boron and carbide forming elements are added, the ultra-low carbon bainite can be obtained, SA633 Gr A high-strength structural steel which has high strength and good plasticity and toughness.
In the first ten days of February 2020, the key statistics show that steel enterprises produce a total of 19.3943 million tons of crude steel, 17.9747 million tons of pig iron, 17.5904 million tons of steel and 3.225 million tons of coke. This ten day average daily output of SA633 Gr A high-strength structural steel crude steel is 1939400 tons, down 2.68% on a month on month basis, up 3.16% on a year-on-year basis; steel is 1759000 tons, down 9.09% on a month on month basis, up 2.51% on a year-on-year basis.