Effect of Microadditives on Center Segregation and Mechanical Properties of High-Strength Low-Alloy Steels

Resumo

One of the main tasks of steelmaking is to obtain the necessary thermodynamic conditions that ensure fine and homogeneous solidified microstructure. The relatively economical solution is to feed microadditives into liquid steel. The metallurgical considerations and techniques on the feeding of microadditives are described in the present work. The effect of small addition of reactive fine particles and ultra-high melting point powders on the control of non-metallic inclusions, slab center segregation, and mechanical properties, especially the Z-direction properties, was investigated. The results showed that the microadditives had composite effects on microalloying and modification of inclusions. The segregation of elements in the slab center of high strength steels was remarkably reduced. The mechanical property along the Z-direction of steel plates was greatly improved.