Yazarlar

• Akar, Neset(1)
• Colak, M.(1)
• Colak, Murat(1)
• Ipek, M.(1)
• Kayikci, Ramazan(1)
• Kiraz, A.(1)
• Kocaman, Engin(1)
• Sirin, Selcuk(1)
• Teke, C.(1)

• MakaleAçık Erişim2019Scopus SJRQ2/r/bayburt/13561
  Prediction of critical fraction of solid in low-pressure die casting of aluminum alloys using artificial neural network

  Teke, C.; Colak, M.; Kiraz, A.; Ipek, M.

  Casting simulation programs are computer programs that digitally model the casting of an alloy in the sand, shell, or permanent mold and, then, the cooling and solidification processes. However, obtaining consistent results out of casting modeling depends on the incorporation of many accurate parameters and boundary conditions. Critical Fraction of Solid (CFS), which is one of the most important of these parameters, is defined as the point where solid dendrites do not allow any flow of the liquid metal in the mushy zone. Since the CFS value varies based on many factors, inconsistent results can be experienced in the modeling applications. In this study, the CFS value obtained during the solidification of various commercial aluminum alloys' casting process, carried out using low-pressure die casting method, is predicted by using Artificial Neural Network (ANN) method based on alloy type, grain refiner and modifier additions, initial mold temperature, and pressure level parameters. In the scope of the study, 162 experiments are conducted. The results obtained from the low-pressure die casting experiments using a special model designed for the study are validated by using SOLIDCast casting simulation. The CFS values are obtained in this validation range of 33% to 61%. These CFS values are used in the development of ANN models. Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), and Mean Square Error (MSE) are used to assess the prediction accuracy of the ANN models. Calculated values of MAE, MAPE, and MSE are 0.0188, 7.06%, and 0.0006, respectively. The results show that the proposed ANN model predicts a CFS value with high accuracy.

  AtıfScopus6·WoS6·OpenAlex4

  İncele
• MakaleAçık Erişim2015Scopus SJRQ2/r/bayburt/12491
  Determination of the critical fraction of solid during the solidification of a PM-cast aluminium alloy

  Kayikci, Ramazan; Colak, Murat; Sirin, Selcuk; Kocaman, Engin; Akar, Neset

  During the solidification of aluminium alloys, a flow of the interdendritic liquid through the mushy zone plays an important role in the feedability and shrinkage-driven porosity formation. Therefore, for almost all the studies about casting modelling, a good knowledge of the mushy-zone behaviour is necessary. In this study, the limit of the mushy-zone permeability for permanent-mould (PM)-cast aluminium alloys was investigated. A novel experimental technique was developed to quantify the value of the critical fraction of solid (CFS) at which the interdendritic feeding stops. Grain-refined and non-grain-refined aluminium alloys were used to evaluate the effect of the grain size on the CFS limit of both the non-grain-refined and fully grain-refined alloys. Three different initial mould temperatures were used to find if the mould temperature has any effect on the feeding of a casting. Alloys of varying solidification intervals were also used to determine the critical fraction of solid (CFS) for the feeding limit of solidifying castings. The results showed that the CFS values for solidifying aluminium alloys may vary from 34 % to 57 % depending on the casting conditions. The results also showed that for A356 aluminium-alloy castings the CFS value is not an alloy property, yet it significantly depends on the parameters such as the grain refinement and the modification of eutectic silicon.

  AtıfScopus9·WoS5·OpenAlex9

  İncele