Hi,
I have an experimental tensile curve. This is the engineering stress strain curve right?
I have then converted it to a true plastic strain curve using Abaqus material conversion. Using these values, I have run a tensile simulation.
However, the results that I have obtained seem to replicate more of the true stress strain curve and not the experimental curve.
The load is displacement based where it is pulled by 32 mm which reflects accordingly to the experiment.
I have plotted misses stress vs LE11.(logarithmic strain along x direction ).
The peak stress in the experiment is 50 MPa while the peak stress for the true stress strain is 70 MPa.
I have attached my results below.
From the simulation, I am getting 70 MPa also which is not representative of the experiment.
Is this how its supposed to be or am I skipping something?
Thanks in advance for your help!!
Found the answer. Posting for anyone looking into this. The graphs generated by Abaqus are the true stress strain curve. It should be compared to the true stress strain graphs from the experimental results.
Are you solving this for non linear condition.
If that is the case you can go for true stress strain curve as input. Otherwise, the results looks to be fine. Remember, you have to follow the loads amma boundary conditions, how it was applied for real time. Viz. One end of the micro gripper is fully constrained and other side is subjected to a pull force of required amount.
The engineering stress and strain that you have from the experiment is not based on measured stress and strain at a specific point. Instead it is based on the total force divided by the initial cross-section and based on the total displacement of the specimen divided by the length.
If you want to compare your simulated results with the the expermental results then you need to ensure that you "measure" it in the same way, i.e. you can extract the force and displacement from your simulation and calculate them to stress and strain (i.e. it represents the average stress and strain in the specimen).
The difference between engineering stress and true stress is that the latter is the stress in a localized point which thereby accounts for the reduced cross-sectional area due to necking.
- Badges
- Science topic
- Similar topics
- Engineering
- Mechanical Engineering