English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

During continuous casting the crystallization behavior of a mold slag has a decisive effect on the lubrication and heat transfer between mold wall and steel strand. By means of the Double Hot Thermocouple Technique the crystallization kinetics of a mold slag could be studied in detail over a wide temperature range. TTT and CCT diagrams were obtained and the crystal morphology was determined at different undercooling or cooling rates. The crystalline phase was determined using X-ray diffraction. Experiments with the presence of water vapor in the atmosphere were also conducted. The presence of water vapor increased the nucleation rate and crystal growth rate significantly when compared to experiments carried out in a dry atmosphere. Precipitation of solid crystals also occurred at a temperature above the equilibrium liquidus temperature (1260°C) that is measured in a dry atmosphere. These results suggest that there is significant interaction between water vapor and liquid slags at high temperatures and that the phase diagram for these slags is very sensitive to the equilibrium partial pressure of water vapor in the surrounding atmosphere. for many steelmaking processes. In the continuous casting of steel, mold powder is added continuously to the top of the mold where it melts to a liquid slag. The slag is then subsequently withdrawn in the gap between the mold wall and the solidifying steel strand working as a medium for both lubrication and heat transfer. The slag film closest to the mold, which experiences the highest cooling rate, freezes initially to a glassy layer. The slag film next to the strand remains liquid and between these two layers crystals will start to precipitate. The presence of crystals has a decisive effect on both the lubrication and the heat transfer between the mold and strand. It is well known from classical nucleation theory that the onset of the formation of solid crystals in slags must be a function of cooling rate and that to determine the true crystallization behavior of a slag one must construct either isothermal time temperature transformation diagrams (TTT curves) or continuous cooling transformation diagrams (CCT curves). In addition, the growth rate, morphology and solidified fraction of the slag under varying thermal conditions are important in the determination of the effect of crystallization of slag on heat transfer and rheology.

In situ Observations and Thermal Analysis of Crystallization Phenomena in Mold Slags