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Volume change during solidification is an important concept in achieving of casting soundness. In this work, first, the solidification shrinkage was measured in copper-lead base alloys by a dilatometer which was developed to use for melting and solidification processes. The volume change was measured during primary solidification and monotectic reaction. The macrostructure evaluation of samples was used to explain the volume change results. A shrinkage model was used to explain the volume changes during solidification. In addition, the microsegregation of alloying elements was studied in the alloys. In the second part, the solidification of brass alloys was investigated in different cooling rates. Microstructure evaluation showed that the peritectic transformation occurred as diffusionless (partitionless) as well as the diffusion-controlled transformation. In addition, the volume change was measured in the peritectic alloys. A theoretical analysis was developed to evaluate the volume change effect on the peritectic reaction. Hot crack formation was investigated during the solidification of peritectic steels as a volume change concept during the transformation of ferrite to austenite. A series of in situ solidification experiments was performed using a MTS tensile testing machine combined with a mirror furnace to measure the sample temperature and the force change during solidification. It was observed that a rise in tensile force began with the start of solidification and suddenly dropped. In the last study, the effect of cooling rate and super heat temperature were studied on the precipitation of primary silicon in Al-Si hypereutectic alloys. The liquidus temperature was found to decrease with cooling rate. In addition, the fraction of primary silicon decreased with increasing the cooling rate and the super heat temperature. Furthermore, the morphology of the primary silicon changed as an effect of cooling rate and super heat temperature. It was concluded that the solidification characteristic and silicon morphology relate to the liquid structure.