Identification of Elastoplastic Constitutive Model of GaN Thin Films Using Instrumented Nanoindentation and Machine Learning Technique

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Good article, clear to understand, simulation and experiements are verey well compliance.

The illustrations are arranged unfavorably. Caption on the same page, fig. 6 and make the image more compact fig. 7. Fig. 8 the same size like fig. 6.

Comments on the Quality of English Language

English is correct.

Author Response

The response to the reviewer comments is in the attached file

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Will the deviation between the FEM results and the experimental results be greater when training based on the FEM results? Have you compared the predicted results of the trained model with the experimental results?

Line 109: Should the crystal plane be (001)

Figure 3 is unclear

By comparing Figures 4a and 5, it can be seen that the finite element simulation results are larger than the experimental results. What is the reason for this? Is there any correction?

Figure 6: The figure and its title should be on the same page

Comments on the Quality of English Language

None

Author Response

The response to the reviewer's comments is in the attached file

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The authors used ANN to establish the nano-indentation properties of Galium Nitride (GaN) thin films. The data base used to train the ANN model follows a validated FE model, simulating the nanoindentation experiment.

 

Overall, the paper is well explained. The results presented clearly show the potential of the approach. However, I would strongly suggest that the authors elaborate further the future application and prospect of the proposed model. This will better highlight the scientific significance of the method. Other comments are given below:

 

Comment #1:

Please provide a simple sketch or diagram summarizing the simulated problem, including load, constraints, etc, in section 3.1.

 

Comment #2:

In line 305, what do the authors mean by intrinsic nanoindentation parameters? Please elaborate.

 

Comment #3:

Can the authors provide evidence or literature that justifies the explanation that lateral friction force has a negligible impact on the model? Typically, at nanoscale, macroscopic assumptions might no longer be valid.

 

Comment #4:

The authors highlighted that the load-depth response is sensitive to indenter tip radius. In the present study, will the rigid assumption potentially be a limiting factor for the simulation? Please discuss.

 

Comment #5:

Please improve the quality of the figures, especially figure 7.

Comments on the Quality of English Language

The language is acceptable and easy to follow.

Author Response

The response to the reviewer's comments is in the attached file

Author Response File: Author Response.pdf