arXiv subjects

Soheil Solhjoo

Publications and source records attributed to Soheil Solhjoo.

5 recordsLinked to original sources

arXiv2023

Flow curve approximation using Avitzur's model for barreling compression test

The combination of the Cylindrical Profile Model (CPM) and Avitzur's model is commonly used to determine flow stress curves in material testing using compression test. In this process, stress is corrected for friction using Avitzur's model and the average strain is calculated from CPM. This study proposes a method for estimating strain based on Avitzur's model. The presented case studies demonstrate the impact of this strain correction on the flow curves. The results show that increasing friction leads to higher strain values at the center of the sample due to barreling. The proposed method provides a more accurate interpretation of compression test results.

cond-mat.mtrl-sci↗

arXiv2023

A short note on approximating the critical strain for the onset of dynamic recrystallization

This note provides a MATLAB code to determine the critical strain associated with the onset of dynamic recrystallization. The code takes a closed-form constitutive model and derives the critical strain by solving $\partial^2 θ/ \partial σ^2 = 0$. Moreover, several models that could be used for this purpose are studied.

cond-mat.mtrl-sci↗

arXiv2014

Determination of flow stress and the critical strain for the onset of dynamic recrystallization using a sine function

A new model has been developed to estimate the flow stress under hot deformation conditions up to the peak of the stress-strain curves. The model is constructed on the basis of the general form of sine functions by introducing an additional exponent. Besides, an equation is derived from the model, which could be used to predict the critical strain for the onset of dynamic recrystallization. The model has been examined for a 304 austenitic stainless steel. The estimated flow stress had an average percentage error of %1.66.

cond-mat.mtrl-sci↗

arXiv2014

Two new mathematical models to predict the flow stress at hot deformation

Based on both linear and non-linear estimations of work hardening rate versus strain curves, two mathematical models have been developed to predict the flow curves under hot working conditions up to the peak. The models were tested for a mechanically alloyed Al6063/0.75Al2O3/0.75Y2O3 nanocomposite under different hot forming conditions. The predicted results from both models are found to be in accord with the experimental flow stress curves. However, the linear model (with an average error of 0.81%) predicted the flow stress more accurate than the non-linear model (with an average error of 1.94%).

cond-mat.mtrl-sci↗

arXiv2014

Evaluation of coefficient of friction in bulk metal forming

In this study an upper bound analysis for cylindrical "Barrel Compression Test" (BCT) is developed. BCT method is a very simple method which can be utilized in order to evaluate quantitatively the coefficient of friction by means of just one cylindrical specimen in an upsetting test. The method is checked by a series of finite element method (FEM) simulations and by means of the results of FEM simulations the method is modified.

cond-mat.mtrl-sci↗