Development of New Steel and its Weldability in China
Steel is one of the fundamental materials in modern industry, being widely used in the construction of a variety of structures such as ships, expressways, railways, bridges and buildings. As the most important material for industrial production, society and people’s lives are increasingly dependent on steel. In recent years, with the rapid progress of science and technology, a variety of new steel have been developed in China. These new steel not only greatly improved the performance, but also the welding performance, which greatly improved the level of steel production. This paper aims to present a brief overview of the development of new steel and its weldability in China.
In recent years, driven by scientific and technological progress, new steel have been developed in China. New steels are characterized by high strength and low alloying elements as well as low cost, which made them attractive to the steel industry. This new generation steel also boasts excellent weldability, allowing for greater design flexibility, reduced fabrication costs and improved fabrication speeds. Most of these new steels are high-strength steels (HSS) with yield strength of twice or more than the traditional steels. As a result, their application range is becoming increasingly widespread.
In order to improve the weldability of HSS and other new steel, several aspects need to be addressed. Firstly, the joint design must be optimized for welding. The joint design factors should be taken into account are the weld size, shape, orientation and radiography requirements. Secondly, the proper welding procedure should be adopted. This includes preheating, heat input, interpass temperature, current and voltage, flux and shielding gas, welding speed and electrode selection. Thirdly, welding consumables should be specially chosen for welding HSS steel. The selection of welding consumables depends on the type of steel and the welding process used. Fourthly, careful control should be taken during welding operation, including the monitoring of joint preparation, welding speed and temperature, as well as post-welding heat treatment.
In conclusion, new steel, such as high-strength steels, have been developed in China. These new steels have excellent mechanical properties and weldability. It is important to optimize the joint design and welding procedures, and to choose the appropriate welding materials and perform proper welding processes to ensure good weldability of HSS and other new steel.
