Prediction of Critical Fraction of Solid in Low Pressure Die Casting of Aluminum Alloys Using Artificial Neural Network

Abstract

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 solidi cation 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 de ned as the point where solid dendrites do not allow any ow 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 solidi cation of various commercial aluminum alloys' casting process, carried out using low-pressure die casting method, is predicted by using Arti cial Neural Network (ANN) method based on alloy type, grain re ner and modi er 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.

Solidification analysis for variable thickness aluminum castings: simulation and chill design insights

“…Also, they can include volume changes and temperature estimations during the solidification and cooling of the cast part. Therefore, the prediction of micro and macro porosity, hot spots, and other defects with high accuracy in various casting problems is possible using this combined thermo-volumetric approach [18][19][20].…”

Modeling the Effect of Pour Height, Casting Temperature and Die Preheating Temperature on the Fluidity of Different Section Thicknesses in Permanent Mold Casting of Al12Si Alloys

“…In fluidity tests known as spiral mold or vacuum test, the distance the liquid metal moves before solidifying is considered as a measure of fluidity [39,40]. Many studies on fluidity and casting simulation are available in the literature [41][42][43]. However, due to the fact that the section thickness is constant in these models, alternative fluidity test models are developed due to the differences observed in the results.…”