The Dual Character of MAX Phase Nano-Layered Structure Highlighted by Supersonic Particles Deposition

Round 1

Reviewer 1 Report

Studies presented in the article seem to be interesting. Proposed manuscript is clearly and well-organized. The work may be considered for publication in Coatings but some improvements are recommended, i.e.:

• Section Introduction: the notations [8-13] and [14-21] should be changed. It is suggested to divide them into smaller ranges and discuss in more detail the importance of the cited investigations in viewpoint of the presented research topic. Additionally, last three paragraphs of this section should be summarized in one paragraph presenting briefly the novelty and the purpose of presented research.
• Section 2. should be significantly shortened because looking at this part of the paper one can get an impression that the proposed work constitutes a Review, not a Research Paper. It is good to refer to the other applied methodologies and their results but not in such an extensive manner. It is suggested to refer briefly to the other methodologies applied but during the description of the performed experiments (not necessarily in a separate section).
• The scheme presented in Figure 10. needs to be discussed in few more sentences.
• Section “Conclusions” should be more focused and brief.
• Section “References”: some abbreviations of the journals’ names are written in italics and some not – this should be improved to be consistent.

Author Response

We kindly appreciate the time and effort that you have dedicated to offer us your valuable feedback on our manuscript.

Point 1: Section Introduction: the notations [8-13] and [14-21] should be changed. It is suggested to divide them into smaller ranges and discuss in more detail the importance of the cited investigations in viewpoint of the presented research topic. Additionally, last three paragraphs of this section should be summarized in one paragraph presenting briefly the novelty and the purpose of presented research.

Response 1: We added more information for the notation that you indicated. It is underlined in yellow. We transformed the last three paragraphs.

 

Point 2: Section 2. should be significantly shortened because looking at this part of the paper one can get an impression that the proposed work constitutes a Review, not a Research Paper. It is good to refer to the other applied methodologies and their results but not in such an extensive manner. It is suggested to refer briefly to the other methodologies applied but during the description of the performed experiments (not necessarily in a separate section).

Response 2: We reorganized this part, and the new changes are highlighted in yellow. The methodology needs were provided in more detail and separated from the results.

 

Point 3: The scheme presented in Figure 10. needs to be discussed in few more sentences.

Response 3: We added more sentences for this figure (now figure 3).

 

Point 4: Section “Conclusions” should be more focused and brief.

Response 4: We shortened the conclusions

 

Point 5: Section “References”: some abbreviations of the journals’ names are written in italics and some not – this should be improved to be consistent.

Response 5: We corrected the names of the journals in italics

 

Reviewer 2 Report

The in-hand article deals with MAX-phase coating using cod spray technique. I believe that in its current form, it is more suited as a literature review article with some research contribution from the authors. I also find the arrangement of the manuscript hard to follow. In addition, the methodology needs to be provided in more details than what is currently shown and separated from the results. Other comments are shown below.

- English grammar needs to be strongly revised

Abstract

Abstract needs to be revised. It provides a lot of introductory and less of what the study is all about. Please provide some description on the study, methodology, and general results.

Materials and Methods

The text written in this section is not related to the title of the section. It is purely a literature review. I was really confused about the paper because it states that it is an original article whereas this section clearly shows that it is a literature review. Please note that MDPI requires that the authors obtain permission for reusing any published image with copy rights.

Original results and discussions on Ti3AlC2 MAX phase coating obtained by CS

 This section is a mix between the authors methodology and results. I believe that the authors need to rearrange their manuscript in a much reader friendly manner.

General comment

Please take into consideration that the readers may want to repeat your experiment, and as such please provide sufficient information for them so that they can do so. At the current form it is hard to follow up or even be able to replicate what was done in your study.  

 

Author Response

We appreciate your constructive review that helps us improved the presentation of our research work. The manuscript was reorganized to have the form of research paper and the research methodology was give in more details in part 2. This section was separated by the results.

Point 1: Abstract

Abstract needs to be revised. It provides a lot of introductory and less of what the study is all about. Please provide some description on the study, methodology, and general results.

Reponse1:

For a better understanding of the ceramic-metallic behaviour at supersonic deposition, this paper aims to complement existing literature and to further extend and advance the research in this field. We choose to present this paper in comparison with the up-to-date results from the literature and original results due to the lack of data on Ti₃AlC₂ deposited by Cold Spray (CS). This material has better chemical and thermal stability, shock resistance, high electrical conductivity and low frictional coefficient due to graphite-like structure compared to other MAX phase compounds and can be used in different fields such as biomedical, aeronautic, aerospace, and hard electrical contact.

 

Point 2: Materials and Methods

The text written in this section is not related to the title of the section. It is purely a literature review. I was really confused about the paper because it states that it is an original article whereas this section clearly shows that it is a literature review. Please note that MDPI requires that the authors obtain permission for reusing any published image with copy rights.

Response 2: We had the copyrights for the images, but we decided to rewrite this section. All the modifications are highlighted in yellow.

 

Point 3: Original results and discussions on Ti3AlC2 MAX phase coating obtained by CS

This section is a mix between the authors methodology and results. I believe that the authors need to rearrange their manuscript in a much reader friendly manner.

Response 3: This section contains now results and discussion. The research methodology was added in the part 2.

 

Point 4: General comment

Please take into consideration that the readers may want to repeat your experiment, and as such please provide sufficient information for them so that they can do so. At the current form, it is hard to follow up or even be able to replicate what was done in your study.  

Response 4: We gave the manuscript a different form and the added information is highlighted in yellow.

Reviewer 3 Report

Dear Authors,

the submitted manuscript on CGS of MAX pahses is very interesting, the scientific value of the own research results is high and these sinteresting results deserve publication.

The organization of the manuscript is however completely inappropriate. It presents a strange mixture between a review paper and original research paper and I have the impression that it is in fact an abbreviated version of the main authors PhD thesis.

The introductory part covers information on max phases, the introduction then, however, continues in the materials and methods section which is normally ment to describe the methods used in the original research. Here a compulsory review of existing literature on coating max phases with a lot of details is given.

In the own results section results and discussion are not clearly separated which makes the manuscript very difficult to read.

I would therefore recommend to give the paper a better organized structure.

Put the "two introductory chapters" together in one introduction chapter focus on the results that are really essential in the context with your research.

Give your original research a clear structure in experimental results (just the results !) and a final discussion chapter where anything is evaluated, explained and compared to the state of the art presented in the introductory part.

If you want to keep all the content it may be better to divide the manuscript in two separate papers. 

 

Author Response

We are grateful for your perspective on this important matter and your comments.

 

Point 1: The organization of the manuscript is however completely inappropriate. It presents a strange mixture between a review paper and original research paper and I have the impression that it is in fact an abbreviated version of the main authors PhD thesis.

Response 1: We reorganized the manuscript to have the form of an article and not a review paper. The work done was the basis of a contract with SAFRAN and not a PhD thesis. We choose to present this paper in comparison with the up-to-date results from the literature and original results due to the lack of data on Ti₃AlC₂ deposited by Cold Spray (CS). This material has better chemical and thermal stability, shock resistance, high electrical conductivity and low frictional coefficient due to graphite-like structure compared to other MAX phase compounds and can be used in different fields such as biomedical, aeronautic, aerospace, and hard electrical contact.

 

Point 2: The introductory part covers information on max phases, the introduction then, however, continues in the materials and methods section which is normally ment to describe the methods used in the original research. Here a compulsory review of existing literature on coating max phases with a lot of details is given.

Response 2: We rewrite this part by presenting the research methodology. All the modifications are highlighted in yellow.

 

Point 3: In the own results section results and discussion are not clearly separated which makes the manuscript very difficult to read.

I would therefore recommend to give the paper a better organized structure.

Put the "two introductory chapters" together in one introduction chapter focus on the results that are really essential in the context with your research.

Give your original research a clear structure in experimental results (just the results !) and a final discussion chapter where anything is evaluated, explained and compared to the state of the art presented in the introductory part.

If you want to keep all the content it may be better to divide the manuscript in two separate papers. 

Response 3: All the part that review the literature was taken out from the section 2 and we only let the information concerning the up-to-date literature in table  3 at the beginning of section 3. Now, this section 3 contains the results and discussion in comparison to the literature.

Round 2

Reviewer 2 Report

Dear respected authors,

I would like to start by acknowledging the improvements done on the manuscript, and therefore I recommend accepting the revised version of the manuscript. However, I want you to know that the reviewer role is to help the authors develop their work before it is presented to the scientific society. This means that we are not trying to stop a good work from getting published but rather want it to be stronger before it is introduced to the readers.

I wish you all the best in your future careers.

The Reviewer 

Reviewer 3 Report

Dear Authors, thank your revising the manuscript according to the comments. From my point of view anything is correct now and the "readability" has strongly improved. the quality of the original research was not an issue anyway. the paper can now be published in the present form.