A SVM model to predict the hot deformation flow curves of AZ91 magnesium alloy

Document Type: Research Paper


1 Department of Mechanical Engineering, Birjand University of Technology, POBOX 97175-569, Birjand, Iran

2 Department of Computer Engineering and Information Technology, Birjand University of Technology, POBOX 97175-569, Birjand, Iran

3 No affiliation


In this work, a support vector machine (SVM) model was developed to predict the hot deformation flow
curves of AZ91 magnesium alloy. The experimental stress-strain curves, obtained from hot compression
testing at different deformation conditions, were sampled. Consequently, a data base with the input
variables of the deformation temperature, strain rate and strain and the output variable of flow stress was
prepared. To develop the support vector machine (SVM) model, the overall data was divided into two
subsets of training and testing (randomly selected). Root mean square error (RMSE) criterion was used to
evaluate the prediction performance of the developed model. The low RMSE value calculated for the
developed model showed the robustness of it to predict the hot deformation flow curves of tested alloy. Also, the performance of the SVM model was compared with the performance of some previously used constitutive equations. The overall results showed the better performance of the SVM model over them.


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