Welding technology as a traditional process after a century of development, its field of application involves all walks of life, nearly a hundred kinds of welding processes, mechanical manufacturing, aerospace, automotive, electronics and other industries have become the other connections can not be replaced technology. In particular, China is still in the process of industrialization, steel production and consumption, according to the first in the world, and welding technology still plays a very important role. Throughout the industrialized countries, the iron and steel power with Welding Wires

Hot-rolled thick plate products are mainly used in shipbuilding, building structures, bridges, boilers and pressure vessels, transport pipeline, offshore platform, construction machinery and other important occasions, increasing product quality Welding Material. This requirement is reflected in the following aspects:

(1) meet the strength, toughness index requirements;
(2) excellent service performance, including high resistance, low temperature performance, fatigue resistance, resistance to media corrosion;
(3) good welding performance, including a wide range of welding process adaptability, high crack resistance, applicable to large heat input welding;
(4) compliance with the regulations;

Which is one of the main requirements for weldability, steel production enterprises in their efforts to solve the key technologies. Micro-alloyed steel products to improve and enhance the weldability core.

Smelting and rolling technology advances

1 pure steel technology

Micro-alloying can not be separated from the overall progress of the metallurgical technology, hot metal pretreatment, steelmaking, ladle refining and vacuum refining refining technology, much lower than the previous low carbon steel content of impurity elements make steel in S, P, etc. and low-alloy steel.

To performance, for example, the pure steel smelting technology to achieve the following levels:

Solidification cracking incidence with a significant reduction of the impurity elements, along with greatly reduced, and no longer be the focus of attention and research.

Due to the structural design requirements of use, the performance of the steel sheet thickness direction can not be ignored. Elimination of the billet middle segregation technology is getting more sophisticated, and greatly reduce the degree of segregation, improved Z-thick plate performance.