The paper presents a detailed description of the process of creation of a surface alloy layer (using high-carbon ferrochromium) on the cast steel casting. The mechanism of the surface alloy layer is based on the known theories [5,6]. The proposed course of formation of the layers has been extended to decarburization stage of steel. The research included proving the presence of carbon-lean zone. The experiment included the analysis of the distribution of elements and microhardness measurement.

The paper presents the results of simulation of alloy layer formation process on the model casting. The first aim of this study was to

determine the influence of the location of the heat center on alloy layer’s thickness with the use of computer simulation. The second aim of

this study was to predict the thickness of the layer. For changes of technological parameters, the distribution of temperature in the model

casting and temperature changes in the characteristic points of the casting were found for established changes of technological

parameters. Numerical calculations were performed using programs NovaFlow&Solid. The process of obtaining the alloy layer with good

quality and proper thickness depends on: pouring temperature, time of premould hold at the temperature above 1300o

C. The obtained

results of simulation were loaded to authorial program Preforma 1.1 in order to determine the predicted thickness of the alloy casting