Reference no: EM132460046
Theory of plasticity Assignment -
Report Assignment 1 -
1. Experimental data from low cycle fatigue tests at constant strain amplitudes are given by pairs of stress-strain amplitude values corresponding to peaks of hysteresis loops at half-life. Convert to the true stress true plastic strain values. Consider elasticity modulus from the hysteresis loop of assignment 3.
2. Perform the optimization task by a non-linear least square method to obtain σY, C1, C2 and γ1 of Chaboche plasticity model (CHAB in Ansys), whereas use the experimental points from the task 1. Use assumption γ2=0.
3. In Ansys APDL mechanical simulate the hysteresis loops with the strain amplitude of 1%, 1.75% and 2.5%. Use the LINK180 element in the FEA. Compare the results of FEM with the cyclic stress-strain curve and with the hysteresis loop from the assignment 3. Try to change number of substep settings to study its influence on accuracy (i.e. number of substep corresponding to 2, 16, 48, etc).
Report Assignment 2 -
1. Experimental data from the tensile test are given by pairs of axial stress-axial strain values. Convert these data to the true stress - true plastic strain values.
2. Perform the optimization task by a non-linear least square method to obtain σY, C1, C2 and γ1 of Chaboche plasticity model (CHAB in Ansys), whereas use the experimental points from the task 1. Use assumption γ2=0.
3. In Ansys APDL Mechanical simulate the test on the specimen below. Use the PLANE STRESS analysis in the FEA. Consider three loading modes - tension, shear and combination of both. Consider maximally 10% of equivalent strain for evaluation.
Report Assignment 3 -
1. Experimental data from the low-cycle fatigue test at a constant strain amplitude are given by pairs of stress-strain values corresponding to the half-life hysteresis loop (columns B and C). Convert to the true stress true plastic strain values. Consider elasticity modulus from the hysteresis loop.
2. Perform the optimization task by a non-linear least square method to obtain σY, C1, C2 and γ1 of Chaboche plasticity model (CHAB in Ansys), whereas use the experimental points from the task 1. Use assumption γ2=0.
3. In Ansys APDL mechanical simulate the hysteresis loops with the strain amplitude of 0.7%, 1.35% and 2.5%. Use the LINK180 element in the FEA. Compare the results of FEM with the cyclic stress-strain curve (the assignment 1) and with the hysteresis loop. Try to change number of substep settings to study its influence on accuracy (i.e. number of substep corresponding to 2, 16, 48, etc).
Report Assignment 4 -
1. Experimental data from low cycle fatigue tests at constant strain amplitudes are given by pairs of stress-strain amplitude values corresponding to peaks of hysteresis loops at half-life. Convert to the true stress true plastic strain values. Consider elasticity modulus from the hysteresis loop of assignment 5.
2. Perform the optimization task by a non-linear least square method to obtain σY, C1, C2 and γ1 of Chaboche plasticity model (CHAB in Ansys), whereas use the experimental points from the task 1. Use assumption γ2=0.
3. In Ansys APDL mechanical simulate the hysteresis loops with the strain amplitude of 1.5%, 2% and 2.5%. Use the LINK180 element in the FEA. Compare the results of FEM with the cyclic stress-strain curve and with the hysteresis loop from the assignment 5. Try to change number of substep settings to study its influence on accuracy (i.e. number of substep corresponding to 2, 16, 48, etc).
Report Assignment 5 -
1. Experimental data from the low-cycle fatigue test at a constant strain amplitude are given by pairs of stress-strain values corresponding to the half-life hysteresis loop (columns B and C). Convert to the true stress true plastic strain values. Consider elasticity modulus from the hysteresis loop.
2. Perform the optimization task by a non-linear least square method to obtain σY, C1, C2 and γ1 of Chaboche plasticity model (CHAB in Ansys), whereas use the experimental points from the task 1. Use assumption γ2=0.
3. In Ansys APD Mechanical simulate the low-cycle fatigue test with non-zero mean stress of 175MPa and stress amplitude of 275MPa. Experimental ratcheting curve is clear from the Fig.2. Create the FE model of testing part only (length 10mm, diameter 5mm). Use the truss element LINK180. A suitable choice of g2 will be necessary to predict the ratcheting correctly.
Report Assignment 6 -
1. Experimental data from the low-cycle fatigue test at a constant stress amplitude and a non-zero mean stress are given by pairs of stress-strain values (columns B and C). Convert to the true stress true plastic strain values.
2. Perform the optimization task by a non-linear least square method to obtain σY, C, γ, Rinf and b of combined hardening model - Armstrong-Frederic+NLISO (CHAB1term and NLISO in Ansys), whereas use the experimental points from the task 1.
3. In Ansys APDL mechanical simulate the ratcheting test. Use the LINK180 element in the FEA. Compare the results of FEM with the experimental results. Try to change number of substep settings to study its influence on accuracy (i.e. number of substep corresponding to 2, 16, 48, etc).
Report Assignment 7 -
1. Experimental data from the tensile test are given by pairs of axial stress-axial strain values. Convert these data to the true stress - true plastic strain values.
2. Perform the optimization task by a non-linear least square method to obtain σY, C1, C2 and γ1 of Chaboche plasticity model (CHAB in Ansys), whereas use the experimental points from the task 1. Use assumption γ2=0.
3. In Ansys APDL mechanical simulate the tensile test. Use the LINK180 element in the FEA. Compare the results of FEM with the experimental results. Try to change number of substep settings to study its influence on accuracy (i.e. number of substep corresponding to 2, 16, 48, etc).
Report Assignment 8 -
1. Experimental data from the low-cycle fatigue test at a constant strain amplitude are given by pairs of stress-strain values corresponding to the half-life hysteresis loop (columns B and C). Convert to the true stress true plastic strain values. Consider elasticity modulus from the hysteresis loop.
2. Perform the optimization task by a non-linear least square method to obtain σY, C1, C2 and γ1 of Chaboche plasticity model (CHAB in Ansys), whereas use the experimental points from the task 1. Use assumption γ2=0.
3. In Ansys APDL Mechanical simulate the low-cycle fatigue test with non-zero mean stress of 155MPa and stress amplitude of 645MPa. Experimental ratcheting curve is clear from the Fig.2. Create the FE model of testing part only (length 10mm, diameter 5mm). Use the truss element LINK180. A suitable choice of γ2 will be necessary to predict the ratcheting correctly.
Note - Should be done in excel and ansys APDL. Need Report Assignment 4. Need a report for all questions.
Attachment:- Assignment File.rar