Abstract
In order to improve the solidification structure of type 430 steel, alloying and inoculation were tested.
Among used alloying elements, Ti is most effective for formation of equiaxed zone, and this effect is considered to be attributed to TiN as nuclei. Ratio of equiaxed zone is related to quantity of TiN.
Co-borate and other borates induce the local temperature drop by thermal decomposition in liquid steel, and then improve the solidification structure. So these inoculators must be used at casting stage.
