Assessment of the Low Alloy Cast Steel Inoculation Effects with Chosen Additives

Structure, and thus the mechanical properties of steel are primarily a function of chemical composition and the solidification process which can be influenced by the application of the inoculation treatment. This effect depends on the modifier used. The article presents the results of studies designed to assess the effects of structural low alloy steel inoculation by selected modifying additives. The study was performed on nine casts modeled with different inoculants, assessment of the procedure impact was based on the macrostructure of made castings. The ratio of surface area equivalent to the axial zone of the crystals and columnar crystals zone was adopted as a measure of the inoculation effect

Rejection in Łukasiewicz's and Słupecki's Sense

The idea of rejection originated by Aristotle. The notion of rejection was introduced into formal logic by Łukasiewicz [20]. He applied it to complete syntactic characterization of deductive systems using an axiomatic method of rejection of propositions [22, 23]. The paper gives not only genesis, but also development and generalization of the notion of rejection. It also emphasizes the methodological approach to biaspectual axiomatic method of characterization of deductive systems as acceptance (asserted) systems and rejection (refutation) systems, introduced by Łukasiewicz and developed by his student Słupecki, the pioneers of the method, which becomes relevant in modern approaches to logic

Development of flight bar conveyors and coal ploughs in Poland

W artykule omówiono rozwój górniczych przenośników zgrzebłowych i strugów węglowych w Polsce. Przedstawiono historię ich rozwoju od pierwszego zastosowania do chwili obecnej. Podano podstawowe parametry techniczne ścianowych i podścianowych przenośników zgrzebłowych i strugów wraz z okresami ich użytkowania. Sformułowano kierunki rozwoju tych maszyn, jakie zdaniem Autorów należy podjąć, aby sprostać wymaganiom górnictwa węglowego.Development of mine flight-bar conveyors and coal ploughs in Poland is discussed. The history of their development from the first use until now is presented. Basic technical parameters of AFCs, BSLs and coal ploughs as well as their life are given. Directions of development of these machines that, according to the authors, should be undertaken to meet the requirements of coal mining industry are formulated

Structure of low-alloy constructional cast steel - a quantitative analysis of impurities

The mechanical properties of cast steel are primarily a function of chemical composition and solidification conditions i.e. primary structure, however, a significant role also plays its quality understood as purity metallurgical i.e. as small as possible content of harmful components of the structure. In work the results of porosity and non-metallic inclusions in steel cast structure quantity analysis are presented.A function which coefficient can be treated as parameters of unwontedstructurecomponent was statistically fittedto histograms of impurities distribution. The influence of O, N, P and S content on approximation function coefficients was analyzed

Stereological parameters of carbides on section of casting made from modified chromium cast iron

W artykule przedstawiono analizę parametrów stereologicznych węglików na przekroju odlewu modelowego wykonanego z modyfikowanego (mieszanina FeNb+FeV+MZR) żeliwa chromowego odpornego na zużycie ścierne . Zaobserwowano skokową zmianę niektórych parametrów stereologicznych węglików w pewnej odległości od powierzchni odlewu.The analysis of stereological parameters of carbides on the section of the model casting made from modified (the mixture FeNb+FeV+RE) wear resistance chromium cast iron was introduced in the article. The jump change of some stereological parameters of carbides in certain distance from the surface of the casting was observed

The influence of chosen modifiers on stereological parameters of carbides of chromium cast iron

W artykule przedstawiono wyniki badań stereologii węglików w modyfikowanym żeliwie chromowym odpornym na zużycie ścierne. W składzie modyfikatorów były następujące pierwiastki: bor, niob, wanad, cer i lantan (MZR), azot. W tabelach i na wykresach pokazano wpływ użytych modyfikatorów na takie parametry stereologiczne węglików jak: wielkość, obwód, współczynnik kształtu i udział objętościowy.The results of investigations of stereological carbides in the modified wear resistance chromium cast iron resistant were introduced in the article. There were following elements: boron, niobium, vanadium, cerium and lanthanum (RE), nitrogen in the composition of modifiers. The influence of used modifiers on such stereological parameters of carbides as: size, perimeter, shape coefficient and volume fraction was showed in tables and on diagrams

Non-metallic Inclusions in Cast Steel Melted in a Small Induction Furnace

Czynnikiem decydującym o jakości wielu stopów w tym szczególnie staliwa jest ilość, wielkość i rodzaj wtrąceń niemetalicznych. W prezentowanej pracy podjęto próbę określenia jak wpływają skład chemiczny, dodatki stopowe oraz sposób prowadzenia wytopu na ilość i rodzaj wtrąceń niemetalicznych.Determinant of the quality of many alloys in particular cast a number of magnitude and type of non-metallic inclusions. In the present study attempts to determine how they affect the chemical composition, alloying elements and the manner in which the melt of the number and type of non-metallic inclusions