Comparison analysis of failure behavior of spherical punch hitting the rupture plate with different material properties using Hypermesh and Radioss

Objective: To analyze and compare the 7 cases of a spherical ball hitting the rupture plate with different materials and properties.

• Given:

Case set up and Execution:

Case 1: 

1. Open the FAILURE_JOHNSON_0000.rad file.

2. Change the shell element properties.

3. Run the radioss analysis and name the file as Law2_epsmax_failure.

4. Now check whether the energy and mass error is less than 15%.

5. Now open Hyperview and select .h3d file.

6. Select contour-von mises-simple method and click apply.

7. Now select multi-window and open .T01 file in Hypergraph to plot the graphs.

Case 2:

1. Open the Law2_epsmax_failure_0000.rad file.

2. In Failure Johnson card change Ifail_sh=1, Dadv=1, Ixfem=2.

3. Run the radioss analysis and name the file as Law2_epsmax_crack.

4. Now check whether the energy and mass error is less than 15%.

5. Now open Hyperview and select .h3d file.

6. Select contour-von mises-simple method and click apply.

7. Now select multi-window and open .T01 file in Hypergraph to plot the graphs.

• As the failure criterion card property changed. The material is subjected to load condition the transformation of the load as the material cracks and deformation of the model is changed a lot and is noticeable hence the failure of the material is as assigned with change. As when the material with certain elastic limit the M2 law which is assigned with failure criteria Ifail_sh as 2 then the simulation shows the elements are cracked and is deleted as within the certain limit in case1, but in case2 the failure criteria is changed to Ishel_sh to 1 as it defined to create or delete the element according to the loading conditions and the applications.
• As the difference in the flow in energy at the dissipation required in order to delete the elements represented by high energy usage. Hence the kinetic energy is peaked that the element cracked split from the maim model component and thus leads in high kinetic at that area of action.

Case 3:

1. Open the Law2_epsmax_crack_0000.rad file.

2. Delete the failure johnson card.

3. Run the radioss analysis and name the file as Law2_epsmax_nofail.

4. Now check whether the energy and mass error is less than 15%.

5. Now open Hyperview and select .h3d file.

6. Select contour-von mises-simple method and click apply.

7. Now select multi-window and open .T01 file in Hypergraph to plot the graphs.

Case 4:

1. Open the Law2_epsmax_nofail_0000.rad file.

2. Remove the EPS_p_max value.

3. Run the radioss analysis and name the file as Law2.

4. Now check whether the energy and mass error is less than 15%.

5. Now open Hyperview and select .h3d file.

6. Select contour-von mises-simple method and click apply.

7. Now select multi-window and open .T01 file in Hypergraph to plot the graphs.

Case 5:

1. Open the Law2_0000.rad file.

2. Change the card image to Law1 i.e, M1_ELAST and assign the properties as mentioned in video.

3. Run the radioss analysis and name the file as Law1.

4. Now check whether the energy and mass error is less than 15%.

5. Now open Hyperview and select .h3d file.

6. Select contour-von mises-simple method and click apply.

7. Now select multi-window and open .T01 file in Hypergraph to plot the graphs.

• In this case, the M1 law of material is applied to the material as with the same aluminum properties which define the material with the elastic property. In such case the simulation shows the materials are elastic that expands and the stress due to load is absorbed by the model. Hence the energy error is low when compared to M2 law with the definition of elastoplastic material. The internal energy with the total energy increases respectively and hence the stress increases. So as the kinetic energy from the ball structure which applies the load on the modeled component is converted to an elastic stretch of the component which stores the energy given by the element.

Case 6:

1. Open the Law1_0000.rad file.

2. Create Law36 card i.e, M36_PLAS_TAB and assign the properties as mentioned in video.

3. Create a test curve with values as mentioned in the video.

4. Run the radioss analysis and name the file as Law36.

5. Now check whether the energy and mass error is less than 15%.

6. Now open Hyperview and select .h3d file.

7. Select contour-von mises-simple method and click apply.

8. Now select multi-window and open .T01 file in Hypergraph to plot the graphs.

• In this method of simulation, the applied material property for the model is LAW 36 which is elastic-plastic as this is the most commonly used material property in industrial analysis in which the output can be recovered as regards to the data from the engineering lab data as the data analyzed manually. Hence In here, the lab data is assumed as the lab data which gives a certain plot graph that has been loaded into the curve card in the model.

Case 7:

1. Open the Law27_0000.rad file.

2. Change the shell properties to recommended properties.

3. Run the radioss analysis and name the file as Law27.

4. Now check whether the energy and mass error is less than 15%.

5. Now open Hyperview and select .h3d file.

6. Select contour-von mises-simple method and click apply.

7. Now select multi-window and open .T01 file in Hypergraph to plot the graphs.

• This material property is of isotropic elastoplastic as which has the plastic region is narrow hence this is a combination of elastic-plastic and brittle failure models. Energy error varies between -0.3% to 1.2% as this material is defied to be brittle material as long as the elements undergo deformation after elastic limit the element gets delete so that no energy is required to delete that element. As the von mises stress is low because of the deletion of the material element according to the property limit that can sustain the energy applied on the component.

Result and Conclusion:

• It can be observed that Law 2 and Law 27 are equal. Each and every material have a different property. The choice of the material depends upon the usage of applications. Certain conditions are analyzed by comparing the results and are tabulated.

The following table shows the results that were obtained:

• If Ixfem value is set to 0 the elements will get deleted and if it\'s set to 1 element will get cracked
• EPS_p_max value should be selected properly because once the elements reach this value they will get either deleted or cracked.
• Rupture plate with elastic material has high von-mises stress.
• No breakage is observed in Case 5, which helps to reduce costs and so on for the company.
• Change in values in Case 2 resulted in more crack propagation.
• The removal of fail_johnson card in Case 3 resulted in breaking of material and removal of EPS_p_max value in Case 4 resulted in material failure.
• So the cases of Law1 and Law2 properties will be preferable to run the simulations and even considerable energy was observed.

Thus, all the points mentioned in the objective are successfully carried out using Hypermesh, and Radioss.