Cyclic tests - tension compression torsion

[svishal03]

Hi,

I have got experimental data for a steel material for a cyclic test perfoemd in the following scenario:

0-1% Torsion followed by
0-1% strain Tension followed by
1-2% Torsion followed by
1% to 0 % compression followed by
2 to 3% torsion followed by
0 to -1% compression followed by
3 to -1% torsion followed by
-1 to 0% tension followed by
-1 to 0% torsion

I'm attaching the figure- that is: the stress strain curve for the tension compression cycle i.e for the cycle corresponding to 0-1% strain- 1% to 0% compression - 0% to -1% compression and -1 to 0% tension.

I have indicated the branch corresponding to loading and unloading in the figure that I'm attaching.

I'm currenly not able to establish contact with the experimentologist- meanwhile could anyone please let me know what does the flat portion indicate? (I have marked the portion).

The fattached file is named flat_portion.jpg.

I shall be grateful if helped.

Vishal

 

[eljose79]

Hi Vishal,

Thank you for sharing your experimental data and the stress-strain curve for the tension-compression cycle. Based on the information provided, it appears that the experiment was performed with multiple loading and unloading cycles, starting with torsion and followed by tension, compression, and torsion again. The flat portion on the stress-strain curve could indicate a period of no applied stress, where the material is allowed to relax or undergo creep deformation. This could be due to the unloading of the previous torsion or compression cycle, or a period of no applied stress during the experiment. Without further information on the experimental setup and conditions, it is difficult to determine the exact cause of the flat portion.

However, it is important to note that the flat portion does not necessarily indicate a lack of data or an error in the experiment. It could be a natural part of the material's behavior and could provide valuable insights into its mechanical properties, such as its ability to withstand creep deformation. I would suggest reaching out to the experimentologist for more information on the experimental setup and conditions to better understand the significance of the flat portion in your data.

In addition, it would also be helpful to plot the data for the other loading and unloading cycles to see if the flat portion appears in those cycles as well. This could provide further insights into the material's behavior under different loading conditions.

I hope this helps and I wish you the best of luck with your research.