Assignment 4

Objective:

1 To learn various materials and their properties in detail from structural deformation consideration.

2 To learn material failure criteria, Crack propagation criteria, and Ultimate strength point variations.

3 To learn Interrelation between practical failure and Simulation breakage of the model.

4 To learn the Cycle time response over the various Input changes.

Case 1: Esp max =0 & No failure.

Setup:

• Imported the Johnson 0000.rad model
• Deleted the Failure Johnson card & updated the Eps max value to 0.
• Run the model & obtained various results.

Results & Discusion:

• Eps Max = 0 means Ultimate tensile strength point shifted to the default value which is infinite that indicates material is never gonna get failed.
• Material behaviour found to be similar to the elastic body causing Stress value increased to 424Mpa.
• Cycle time found to be 148.81 S with 48737 cycles.

Case 2: Esp max =0.40 & No failure.

Setup:

• Imported the Johnson 0000.rad model.
• Deleted the Failure Johnson card & updated the Eps max value to 0.40.
• Run the model & obtained various results.

Results & Discusion:

• Eps Max = 0.40 means that material will fail once its stress value reaches 40% beyond its yield stress which is nothing but its Ultimate tensile strength point.
• Material behaviour found to be Elasto Plastic body with a Stress value of 374 Mpa.
• Material collapsed like a tearing effect while sudden vanishing or deletion of elements was observed. Crack propagation was not smooth.
• Cycle time found to be 148.81 S with 48737 cycles.

Case 3: Esp max =0.40 & Default failure.

Setup:

• Imported the Johnson 0000.rad model.
• Updated the Eps max value to 0.40 & Kept Failure Johnson card in the default state.
• Run the model & obtained various results.

Results & Discusion:

• Eps Max = 0.40 means that material will fail once its stress value reaches 40% beyond its yield stress which is nothing but its Ultimate tensile strength point But now material was under constrained of Johnson failure card.
• Material behaviour found to be Elasto Plastic body with a Stress value of 244 Mpa.
• Material collapsed like tearing effect while few vanishing or deletion of the element was observed. Crack propagation was quite smooth.
• Due to Johnson failure tremendous reduction in Cycle time was found equals to 4 S with 49304 cycles.

Case 4: Esp max =0.40 & IEXM failure.

Setup:

• Imported the Johnson 0000.rad model.
• Changed the Eps max value to 0.40 & updated Failure Johnson card by IEXm = 1 & Dadv=1.
• Run the model & obtained various results.

Results & Discusion:

• Eps Max = 0.40 means that material will fail once its stress value reaches 40% beyond its yield stress which is nothing but its Ultimate tensile strength point But now material was under constrained of Johnson failure card.
• Material behaviour found to be Elasto Plastic body with a Stress value of 400 Mpa.
• Material collapsed like tearing effect with no vanishing or deletion of the element was observed. Crack propagation was very smooth.
• Due to Johnson failure tremendous reduction in Cycle time was found equals to 9 S with 49212 cycles.

Case 5: Law 1 Elasto

Setup:

• Imported the Johnson 0000.rad model.
• Deleted the Failure johnson card & Updated the material card with Law 1 Under which Rho = 0.0028, E = 71000, Nu = 0.33 values
• Run the model & obtained various results.

Results & Discusion:

• Material behaviour was found to be Elastic body like rubber with a Stress value of 10890 Mpa.
• Elemental collapsing doesn’t happen cause the material to undergo such a huge stress value.
• Cycle time observed was 76.4 S with 47969 cycles.

Case 6: Law 36 Plas

Setup:

• Imported the Johnson 0000.rad model.
• Deleted the Failure johnson card & Updated the material card with Law 36 Under which Rho = 0.0028, E = 71000, Nu = 0.33 values
• Updated N func library by adding Lab tested Curve tab for stress-strain values.
• Run the model & obtained various results.

Results & Discusion:

• Material behaviour was found to be Real Elastoplastic body with a Stress value of 801 Mpa.
• Elemental collapsing happen with realistic effect and response.
• Cycle time found to be 84.16 S with 53155 cycles.

Case 7: Law 27 Plas Brit

Setup:

• Imported Law 27 0000.rad model.
• All the required plas brit data was available in material tab While updated the property tab by desired shell properties like 24 QEPH Smstrn = 2, Ish3n =2, N=5, Ithick = 1 & iplas = 1.
• Run the model & obtained various results.

Results & Discusion:

• Material behaviour was found to be perfect brittle crystalline material with a Stress value of 260 Mpa.
• Elemental collapsing happen with realistic effect and response.
• Cycle time found to be 80.15 S with 49508 cycles.

Final Conclusion & Tabulation:

• Espmax value tells us the ultimate strength shift with respect to yield point. As Value goes away from 0, Ultimate strength value increases causing an increase in stress generation. While 0 is default value indicating infinite strength means material never gonna fail.
• Presence of Failure johnsons card neglects the presence of material esp card value. IEXm = 1 value prevents sudden element deletion and exhibits proper crack propagation.
• Law 1 explains Elastic behaviour, Law 2 gives Elaso plastic, Law 36 Real elastoplastic while Law 27 explains Plastic brittle material.

Model Name	Cycle time (S)	No. of cycles	Energy error	Mass error	Displacement (mm)	Von Misses Stress(MPa)	Energies(J) TE,IE	Forces(N) NF
1) Esp = 0 & no failure	148.81	48737	3%	0.62e5	5.01	424	7000	20000
2) Esp = 0.40 & no failure	148.8	48737	3%	0.62e5	5.32	374	45000	10000
3) Esp = 0.4. & Default failure	78.4	49304	1.1%	0.38e5	5.62	244	40000	9000
4) Esp = 0.40 & Iexm failure	78.9	49212	7.6%	0.40e5	5.56	400	40000	11000
5) Law 1 Elastic	76.4	47969	1.3%	0.85e6	5	10890	900000	500000
6) Law 36 Plas	84.16	53155	-1.3%	0.44e5	68.6	801	40000	20000
7) LAw 27 Plas Brit	80.15	49508	0.8%	0.29e5	16.7	260	30000	8000