Forming of Positive Macrosegregations during Steel Ingot Solidification
It is known that the degree of positive segregations in upper part of ingots is very sensitively dependent upon the enriched liquid velocity. In this paper, relationship between chemical composition of steel and liquid density changes are considered.Besides, the influence of the primary and secondary arm spacing (λ<sub>1</sub>, λ<sub>2</sub>) on the liquid flow velocity, <I>i.e.</I> intensity of positive macrosegregations, was studied, using examples from 3-tone ingots, for different grades of steel. The elements as W, Ni, Mo, Cr, decreases the effect of density changes (<I>d</I>ρ<sub>L</sub>/<I>df</I><sub>L</sub>), <I>i.e.</I> they have smaller tendency to segregation forming. Global intensity of positive macrosegregations, S<sub>i</sub><sup>g</sup>, which can be calculated by integration of local macrosegregations degree, depends approximately linearly on the liquid flow velocity.
- ISIJ international
ISIJ international 39(4), 329-334, 1999-04-15
The Iron and Steel Institute of Japan