TY - JOUR N2 - Core sands for blowing processes, belong to these sands in which small amount of the applied binding material has the ability of covering the sand matrix surface in a way which - at relatively small coating thickness - allows to achieve the high strength. Although the deciding factor constitute, in this aspect, strength properties of a binder, its viscosity and ability to moisten the matrix surface, the essential meaning for the strength properties of the prepared moulding sand and the mould has the packing method of differing in sizes sand grains with the coating of the binding material deposited on their surfaces. The knowledge of the influence of the compaction degree of grains forming the core on the total contact surface area can be the essential information concerning the core strength. Forecasting the strength properties of core sands, at known properties of the applied chemically hardened binder and the quartz matrix, requires certain modifications of the existing theoretical models. They should be made more realistic with regard to assumptions concerning grain sizes composition of quartz sands and the packing structure deciding on the active surface area of the contacts between grains of various sizes and - in consequence - on the final strength of cores. L1 - http://journals.pan.pl/Content/102042/PDF/afe-2017-0085.pdf L2 - http://journals.pan.pl/Content/102042 PY - 2017 IS - No 3 DO - 10.1515/afe-2017-0085 KW - Moulding sand KW - Core sand KW - Blowing method KW - Core properties A1 - Dańko, R. PB - The Katowice Branch of the Polish Academy of Sciences VL - vol. 17 DA - 2017 T1 - Validation of the Theoretical Model of Determining the Strength of Cores Made by the Blowing Method UR - http://journals.pan.pl/dlibra/publication/edition/102042 T2 - Archives of Foundry Engineering ER -