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Gating system design is an essential element in casting process which affects significantly the molten metal flow behavior, heat transfer and solidification of the melt. Optimum gating design will lead to a good quality of casting product. One of the major components in gating system is runner. This study was conducted to determine the effect of vortex runner diameter gating system on the mechanical strength of Al-12Si alloy casting. Simulation was conducted to study the behavior of the fluid flow and the results obtained showed close agreement with the results obtained from the experiment. Experimental results showed that the casting product with bigger vortex runner diameter gating system led to the improvement of average bending strength.Keywords: gating system, sand casting, mechanical strength, weibull analysis Układ wlewowy to podstawowy element w procesieodlewania, który znacząco wpływa na płynięcie ciekłego metalu, transport ciepła oraz krzepnięcie metalu. Optymalny układ wlewowy gwarantuje dobrą jakość odlanego produktu. Jednym z głównych elementów układu wlewowego jest kanał wlewowy. Celem pracy było zbadanie wpływu średnicy kanału układu wlewowego na wytrzymałość mechaniczną odlewów ze stopu Al-12Si. Celem zbadania zachowania przecieczy przeprowadzono symulacje i otrzymane wynikiwykazują dobrą zgodność z wynikami otrzymanymi doświadczalnie. Wyniki doświadczeń pokazały, że zastosowanie większej średnicy kanału układu wlewowego prowadzi do poprawy średniej wytrzymałości odlewów na zginanie.

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The properties of Al-Si-Cu cast alloys are strongly affected by eutectic Al-Si and Al-Cu phases. The characteristic parameters of these two phases with additions cerium 1wt % (Ce) and lanthanum1 wt % (La) were investigated in Al-11Si-2Cu near eutectic alloy using computer-aided cooling curve thermal analysis. As a result, the La additive showed the highest (TNAl-Si) while the Ce additive showed very little effect. In addition, the growth temperature (TGAl-Si) is decreased by adding Ce compared to the base alloy and La addition. Additives showed an increase of recalescence magnitude (TRAl-Si). Addition La and Ce increased the nucleation and growth temperature of Al-Cu phase. The microstructure analysis on the silicon morphology showed that 1 wt % La and 1 wt % Ce additions play refiner role in Al-Si-Cu near eutectic alloys. Findings are also confirmed by aspect ratio of eutectic silicon phase.

The evaluation of 0.1 to 1.0% of Ce addition effect on fluidity has been investigated. The fluidity of LM6 has decreased with the Ce addition. The effect of Ce can be shown very clearly with a high amount of 1% wt of Ce. The fluidity length of the composites is shorter than that of the LM6 base material. In spiral mold, the fluidity length is shortened when the weight percentage of Ce content is increased in the base metal LM6. Optical microscope images showed that the 1.0 % of Ce additive led to modification of silica morphology which reduced the fluidity length to 28%. The partial modification of silica can be observed clearly in small amount of Ce but it does not have large affect on the fluidity length.