Keywords

Abstract

Foundry sand;

 Cast iron; 

Microstructure; 

Mechanical properties; 

Perlite and bentonite.

Many studies are being carried out on factors such as casting temperature, cooling rate, mold design and, so on due to the effects of casting and solidification conditions on the mechanical properties of the final product. However, given literature, there appears to be no comprehensive study on the effect of casting mold sand components on the mechanical properties of cast iron. From this point of view within the scope of this study, the effects of casting mold sand and binder on the cast iron were investigated. By using silica and olivine as foundry sand at different ratios, bentonite and perlite as binders, the effects of them on the microstructure and the mechanical properties of casting were investigated. The microstructures of the products show that as the cooling rate slows down, the distribution of graphite particles in the structure changes from flakes to nodules. These structural changes are very matched with the results of mechanical properties. Therefore, when the cooling rate decreases, the hardness decreases from 310 HV to 239 HV in all of the groups. Also, the bending strength is going from 971.53 MPa to 487.42 MPa, like in the hardness results. On the contrary, the deformation increases from 13 % to 24 % when cooling rates decreases. This study clearly demonstrates that the products can be obtained by changing the heat conduction coefficient of the casting mold with different mechanical properties from the same molten metal. 

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