A mathematical method for the forecast of the type of structure in the steel static ingot has been recently developed. Currently, the method has been applied to structural zones prediction in the brass ingots obtained by the continuous casting. Both the temperature field and thermal gradient field have been calculated in order to predict mathematically the existence of some structural zones in the solidifying brass ingot. Particularly, the velocity of the liquidus isotherm movement and thermal gradient behavior versus solidification time have been considered. The analysis of the mentioned velocity allows the conclusion that the brass ingots can evince: chilled columnar grains-, (CC), fine columnar grains-, (FC), columnar grains-, (C), equiaxed grains zone, (E), and even the single crystal, (SC), situated axially. The role of the mentioned morphologies is analyzed to decide whether the hard particles existing in the brass ingots can be swallowed or rejected by the solid / liquid (s/l) interface of a given type of the growing grains. It is suggested that the columnar grains push the hard particles to the end of a brass ingot during its continuous casting.

The article discusses the structure of the slag in the liquid state, the properties and interactions within the slag. The analysis of structures occurring in slag suspension were presented with regard to differences in chemical composition in micro-areas. Two different mechanisms for formation of precipitates in Cu-Fe-Pb alloys during extraction were showed.Keywords: decopperised, crystallisation, slag, structure.W artykule omówiono strukturę żużli w stanie ciekłym, oraz właściwości i oddziaływania wewnątrz żużli. Przedstawiono wyniki analiz występujących struktur w żużlu zawiesinowym, w odniesieniu do różnic w składzie chemicznym w mikroobszarach. Wskazano na dwa różne mechanizmy tworzenia wydzieleń stopu Cu-Fe-Pb podczas ekstrakcji. Analysis of the problems IntroductionIncreasing metallurgical yields and improving quality of the metals/alloys requires introducing numerous processes and techniques during designing of solidification, melting and casting. These are, reported in literature, reducing metals oxides present within slags [1][2][3], melt protecting with fluxes [4], melt modification before casting into foundry molds [5,6], riser protecting with insulating sleeves against surplus heat loses [7] as well as considering back-diffusion phenomena in solidifying metals and alloys [8]. The present paper deals with suspension slags of Cu production, their structure, composition, and mechanisms of extraction processes which proceed inside the slags.Suspension slag is formed during the extraction process of copper production in the melting flash. Then-formed suspension slag is directed to the electric furnace-arc where it is decopperisied. Decopperisation causes the reduction of oxides forms of primarily copper, lead and iron and then segregation of a Cu-Fe-Pb alloy. The moment of slag contacting the layer of coke reduction (phase 1), the majority of Cu 2 O is removed and the total copper content of the slag decreases to approx. 2,0%.Over the next 4-5 hours (phase 2) of the process, the content decreases to approx. 0.8%. Following the tapping process (phase 3), the content keeps decreasing and reaches a minimum of approx. 0.5%. The changes of concentration in the slag (particularly in phase 2 and 3) affect the structure and properties what have the decisive impact on the slag suspension decopperisation. The structure of slag in the liquid stateThe properties of the slag are determined by its structure. Slag structure can be described either by the molecular theory [1] or can be analyzed as electrolytes [2]. A. Bydałek and M. Brzózka [3] assumed that the slags in the liquid state were the boundary type of strong electrolyte solutions. In that case slag has ordered construction of the ion and tend to surround cations with oxygen ions. Small ions with high charge (Si 4+ , B 3+ ) strongly attract oxygen and produce a significant density of their immediate environment. Large ions with low charges (Ca 2+ , Na 1+ ) weakly attract oxygen. Tiemkina [9,14] however, pointed that, the creation of a multi-component systems ...

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A vertical cut at the mid-depth of the 15-ton forging steel ingot has been performed by curtesy of the CELSA - Huta Ostrowiec plant. Some metallographic studies were able to reveal not only the chilled undersized grains under the ingot surface but columnar grains and large equiaxed grains as well. Additionally, the structural zone within which the competition between columnar and equiaxed structure formation was confirmed by metallography study, was also revealed. Therefore, it seemed justified to reproduce some of the observed structural zones by means of numerical calculation of the temperature field. The formation of the chilled grains zone is the result of unconstrained rapid solidification and was not subject of simulation. Contrary to the equiaxed structure formation, the columnar structure or columnar branched structure formation occurs under steep thermal gradient. Thus, the performed simulation is able to separate both discussed structural zones and indicate their localization along the ingot radius as well as their appearance in term of solidification time.

The scope of work included the launch of the process of refining slag suspension in a gas oven using a variety of technological additives. After the refining process (in the context of copper recovery), an assessment of the effect of selected reagents at the level of the slag refining suspension (in terms of copper recovery). Method sieve separated from the slag waste fraction of metallic, iron -silicate and powdery waste. Comparison of these photographs macroscopic allowed us to evaluate the most advantageous method of separating metallic fraction from the slag. After applying the sample A (with KF 2 + NaCl) we note that in some parts of the slag are still large amounts of metallic fraction. The fraction of slag in a large majority of the elements has the same size of 1 mm, and a larger portion of the slag, the size of which is from 2 to 6 mm. Definitely the best way is to remove the copper by means of the component B (with NaCl ) and D (with KF 2 ). However, as a result of removing the copper by means of component C (with CaO) were also obtained a relatively large number of tiny droplets of copper, which was problematic during segregation. In both cases we were able to separate the two fractions in a fast and simple manner.