Numerical Simulation Analysis on Surface Quality of Aluminum Foam Sandwich Panel in Plastic Forming

Round 1

Reviewer 1 Report

The following are the comments for the authors to improve the quality of the manuscript.

Major comments

1.       The abstract is too general; more specific information about the methodology and results must be added to the abstract.

2.       Line 33 to 35 is a mixture of two contradicting and out-of-context sentences.

3.       The local straight-face defect is not visible in Fig. 1 b; the authors need to present the view in such a way that the defect should be visible in the figure.

4.       Line 136, “between the five maximum peak” Why only five points were selected and how closely were these points spaced? Five points are too few for such a big surface.

5.       Line 138, “the target surface was taken” how the target surface was defined and what is its location and dimensions?

6.       A complete view of the FE model with boundary conditions must be added.

7.       Figure 2, 3, 4, 8, and 13 needs to be shown in more enlarged views. At the moment, the FEA details such as element distortion/deformation are no visible. Only macro-level details can be seen at the moment. One way could be to show call-outs from the high strain or other critical regions.

8.       Line 246, “Set the distance away from the short edge boundary to d. The…” This process is not clear, show it in the images. Not clear what is short-edge boundary

9.       Please add the captions for the sub-figures in Figures 2, 3, 4, and 8. Without sub-figure captions, these are difficult-to-understand figures.

10.   Line 305, “foam with density of 0.57 g/cm3” here a different density is used compared to Table 2. Was this accounted in the FE model?

11.   Fig 7a show the squeezing of the AFSP at the corners or edges/ends, the thickness is more in the middle while less at the edges. Was this effect captured by the FE models, show cross-sectional figures? How has this phenomenon affected the surface parameters Sa, Sp Sv, etc?

12.   Line 336, why is a different radius (600 mm) selected this time compared to the previous 400 mm?

13.   From section 4.2 onward till section 4.3.1, very limited scientific reasoning is presented for the observed phenomena. The authors are mainly reporting the results only without detailed reasoning. More discussion is required to explain the underlying phenomena of the observed results.

Minor comments

14.   In the abstract, “The finite element model of AFSP multi-point forming (MPF)…”it is not correct to add MPF here as CS and TKD are only related to AFSP and not MPF.

15.   “was established with cubic-spherical (CS) and tetrakaidecahedral (TKD) models as foam structures…” This statement is not clear and misleading, as it currently means that both CS and TKD were used at the same time.

16.   “saddle-shaped were discussed” was not were

17.   “the MPF experiment of AFSP was carried out,….” This statement gives a feeling that the authors only conducted one MPF experiment. Please correct the English accordingly.

18.   “surface defects of experimental AFSP,” surface defects produced in AFSP… or experimental surface defects in AFSP…. English improvements are required

19.   Line 33, “the overall quality is poor.” Poor in terms of what?

20.   “…..produce surface dimpling of the size of the cell.” Line 102 and 103 needs to be rephrased

21.   Link the defects in Fig. 1b with the main surface as call-outs.

22.   Line 177, “….more realistically and effectively.” Provide ref for this.

23.   Line 186, “commercial software ABAQUS…,” I think its ABAQUS / Standard

 

24.   How were the friction coefficients of 0.1 and 0.2 determined?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The article deserves great recognition. Both the theoretical basis and the adjustment of the model to real conditions are described in a very clear and comprehensive way. I would only recommend extending the text with a more precise "technical description of the conditions adopted for modeling". Unfortunately, most of the conclusions are statements, please change them or describe the section rather as a Summary.

In addition, I am asking the authors for a broader description of the model verification and validation process in relation to real research.

In addition, the presented article requires a correction of the title because the current one can be associated rather with roughness, micro-scale quality, etc.

In addition, please highlight what the authors have in mind when writing "surface quality".

In general, the article after minor corrections can be a very interesting position enriching knowledge in the aspect of the presented subject of numerical modeling of the aluminum forming process foam sandwich panels.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

It is a good paper of numerical approximation which allows, through the use of a simulation with finite elements technique, to verify the formation of some typical defects in an aluminum foam sandwich. The aim of the paper is to verify how the formation of such defects can be related to some critical parameters of the panels. The paper is also experimental as the authors used a 3D scanner to experimentally analyze the surface of some panels. This is definitely a strong point of the paper. In the work of numerical approximation there are certainly not many new elements, but the work done is certainly good. It seems that the simulation makes it possible to predict an overall behavior of the panels which is subsequently verified experimentally. I believe that this is a point to be explored as the predictive capacity of a numerical simulation is yet to be verified. In this case it does not seem that the authors have gone beyond what is logically permitted.

The summary is well written and in line with what is written in the text. The bibliography is correct. The conclusions are correct.

The paper can be published in the present form.

Author Response

Dear Editor and Reviewer,

 

Thank you very much for your letter and for the reviewer’s comments on our manuscript entitled “Numerical simulation analysis on surface quality of aluminum foam sandwich panel in plastic forming” (Manuscript ID: metals-2066288). Those comments are all valuable and helpful for revising and improving our paper. Thank you for your hard work.

 

We appreciate for Editors/Reviewers’ warm work earnestly. Once again, thank you very much for your comments and suggestions.

 

Yours sincerely,

Wei-guang Zhang

Reviewer 4 Report

The manuscript appears to be mathematically and experimentally correct and the utilized methods and the proposed models are interesting. I recommend the paper for publication, however, there are some concerns, comments and suggestion should be addressed before publication:

1.     There are grammar and typographic errors. Please correct these errors and further improve the language.

2.     In this paper, how do the authors use 3D to analyze surface quality? Need to talk in detail.

3.     The novelty of this work must be presented in Introduction and Conclusion section very clear.

4.     The results and figures are appropriate however; author should add more physical explanation for the observed results.

5.     What is the importance of the thickness for the considered problem?

6.     What is the criterion to determine the occurrence of mechanical behavior?

 

7.     How to verify the accuracy and correctness of the results?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors have satisfactorily revised the manuscript. 

Please recheck the figure number, e.g., two Figures are numbered as Figure 12.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

After the corrections have been made, the article may be approved for publication.

Author Response

Dear Editor and Reviewer,

 

Thank you very much for your letter and for the reviewer’s comments on our manuscript entitled “Numerical simulation analysis on surface quality of aluminum foam sandwich panel in plastic forming” (Manuscript ID: metals-2066288). Those comments are all valuable and helpful for revising and improving our paper. Thank you for your hard work.

 

We appreciate for Editors/Reviewers’ warm work earnestly, and hope that the above correction will meet approval. Once again, thank you very much for your comments and suggestions.

 

We look forward to hearing from you soon.

Yours sincerely,

Wei-guang Zhang

 

 

Reviewer 4 Report

Acceptable

Author Response

Dear Editor and Reviewer,

 

Thank you very much for your letter and for the reviewer’s comments on our manuscript entitled “Numerical simulation analysis on surface quality of aluminum foam sandwich panel in plastic forming” (Manuscript ID: metals-2066288). Those comments are all valuable and helpful for revising and improving our paper. Thank you for your hard work.

 

We appreciate for Editors/Reviewers’ warm work earnestly, and hope that the above correction will meet approval. Once again, thank you very much for your comments and suggestions.

 

We look forward to hearing from you soon.

Yours sincerely,

Wei-guang Zhang