R. Mohamadi - Department of Mechanical Engineering, Amirkabir University of Technology, No.۲۴,Hafez Ave, Tehran, Iran
A. Fallahi - Department of Mechanical Engineering, Amirkabir University of Technology, No.۲۴,Hafez Ave, Tehran, Iran

In this investigation, the effect of microstructure on ultimate tensile strength (UTS) of dual phase (DP) steels with niobium was investigated. Microstructure consists of: Martensite volume fraction (Vm), ferrite grain size (d) and martensite hardness (HV). These parameters have been correlated with the UTS and are brought out in the form of 3D diagrams. Also, a neural network model based on the Vm, d and HV was used to predict UTS. The results of this investigation show that Vm is the most significant parameter in increasing or decreasing the UTS for this type of steels and there is a good agreement between experimental values and predicted values by artificial neural network (ANN).

microstructure; ultimate tensile strength; dual phase steels; controlled rolling; neural network