Prediction of 2A70 aluminum alloy flow stress based on BP artificial neural network

Recently ,withtherapiddevelopmentofthecompu tationtechnique ,thefiniteelementmethodisappliedmoreandmoretothenumericalsimulationofthemetalformingprocess .Therelationshipbetweenflowstressanddeformationconditionssuchasstrain ,strainratesandtemperatures,whichembodiestheresponseofamaterialtothedeformationparameters ,isveryimportantforthenumericalsimulationbyfiniteelementmethod .Butduringthehotdeformationprocess ,therearemanyfactorsthatinfluencetheflowstressofthemetal .Theeffectsofthesefactorsonthef…

Prediction of 2A70 aluminum alloy flow stress based on BP artificial neural network

The hot deformation behavior of 2A70 aluminum alloy was investigated by means of isothermal compression tests performed on a Gleeble - 1500 thermal simulator over 360 ～480°C with strain rates in the range of 0.01 ～ 1 s- 1 and the largest deformation up to 60%. On the basis of experiments, a BP artificial neural network (ANN) model was constructed to predict 2A70 aluminum alloy flow stress. True strain, strain rates and temperatures were input to the network, and flow stress was the only output. The comparison between predicted values and experimental data showed that the relative error for the trained model was less than ± 3% for the sampled data while it was less than ± 6% for the non-sampled data. Furthermore, the neural network model gives better results than nonlinear regression method. It is evident that the model constructed by BP ANN can be used to accurately predict the 2A70 alloy flow stress.