Research on the Ablation Resistance of TiC Particle-Reinforced Aluminium-Based Composite Coatings on Armature Surface

Round 1

Reviewer 1 Report

Review on the Manuscript entitled:

 Research on the Ablation Resistance of TiC Particle Reinforced Aluminium-Based Composite Coatings on Armature Surface

 Dear Editor,

In this article, the authors have investigated TiC particles which are widely selected as metal material reinforcements with their advantages such as high melting points and high hardness. The authors have shown that the arc impact model of pure aluminum alloy and the arc impact model of TiC particle reinforced aluminum matrix composite coating-pure aluminum alloy were constructed based on molecular dynamics simulation. The ablation resistance of the material was evaluated by analyzing the depth of arc impact, the mass loss of the model, the number of gasification atoms and the surface temperature of the material. The evolution of the microstructure of the material was revealed by surface and subsurface morphology analysis, so as to clarify the ablation resistance mechanism of TiC particle reinforced aluminum matrix composites. In my opinion, the subject of this manuscript is very interesting and applicable in the electromagnetic rail launch process which can help the challenges in economic, technological, and other issues. I recommend this article for publishing in the Coatings; however, it needs some major and minor revisions:

1. Although the subject is applicable, the abstract is more descriptive. Generally, the abstract should include purposes, methods, results and originality/novelty. So, it is better the authors start the abstract with these phrases such as: This work aims to…, This research wants to… etc. Moreover, there is no certain consequences for the readers through these phrases in the abstract: “The evolution of the microstructure of the material was revealed by surface and subsurface morphology analysis, so as to clarify the ablation resistance mechanism of TiC particle reinforced aluminum matrix composites. The results showed that the addition of TiC particles is helpful to improve the impact resistance and ablation resistance of armature.” Please improve the abstract with some concise details.

2. Moreover, the keywords are repetitive the title of the article. Please use more special.

3. Page 1, line 42, please define this abbreviation: “…MA level…”

4. Page 3, lines 135, 136 what is the abbreviation of LAMMPS, and OVITO. Please define it.

5. Would you please explain which software with citation has been used for molecular dynamics simulation?

6. The specification of TiC crystal must be explained. In addition, why the authors have applied the TiC? On the other hand, can the SiC nanostructure be used as the semiconducting specification or other transition metals combined with carbon.  Please illustrate it.

7. Please improve the quality of Figure1. It is not clear.

8. Page 4, line 172: “…Morese potential function…” should be Morse.

9. The subsection of 2.2.1. Potential function setting: “The potential functions include Embedded Atom Method (EAM), Morese potential function, Born-Mayer potential function, The Second Nearest-Neighbor Modified Embedded Atom Method (2NN MEAM), Lennard-Jones potential function, Table potential function and Tersoff potential function” with different potential functions and equations needs the citation.

10. Which force field has been used for your work through molecular dynamic simulation?

11. Why do the authors use the Morse potential for their simulation?

12. As the authors did the electromagnetic analysis, have they investigated the chemical shielding of Ti, C and Al during the interaction based on NMR spectroscopy? Or have they seen any experimental data in this area? The chemical shielding of element improves your result and the quality of your work.

13.Please increase the quality of Figures 5,10,14.  The numbers, and letters in the axes of X and Y are not readable. Also, control the quality of all Figures in your article. 

14. Add one paragraph as the total consequence and discussion at the end of section of Results and Discussion and before the Conclusion. This paragraph can attract the attention of readers and the total viewpoint of your work.

15. However, the categorizing your article is appropriate aspect f different section and subsections.

Author Response

We have made changes and replied to your questions. Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Rail guns have been developed since many decades, with limited success.
The largest versions of electromagnetic launchers have been suggested for the launch of spacecrafts or for transporting lunar or asteroidal material back to Earth orbit. Consequently there is an element of science
fiction in all such work, which has turned out so much more technically demanding than space novel authors have cared to envision. Funding surely is available only from the military sector. This aspect lets me hesitate to continue the review, as weapons research is not advisable material for international research journals.

The report concerns the problem of coating and abrasion reduction on surfaces that are under severe strain by mechanical shear forces as well as hot, dense plasmas. Thus the topic is suitable for MDPI coatings.

What strikes me in the abstract is that the command of English has gaps that need to be repaired.
The first sentence probably should read:
"The electromagnetic rail launch process easily triggers high energy and high heat arcs, and severely damages aluminum alloy systems."
English uses particles "a" and "the" which do not exist in many other languages, but are necessary for the flow of the text. They are missing at several locations in the abstract, and at many more in the text.

The first 6 lines of the introduction do not belong into a science journal. Line 55 is inappropriate, as it propagates militarization as a research objective.

Line 56, delete "scholar"

Line 96, delete hyphen from "ad-vantage"

Line 122, delete the first hyphen from "an-ti-ablation"

Fig. 1, please explain "cytosolic"
The figure would be better readable with text enlargened by at least a factor of two

Line 193, 195 and Tab 3, "Morese potential" or "Morse potential"?

Fig. 2, 3, 4, 5, 6, 7, 8, 9, 10, and so on, use larger lettering, please

Line 262, stating a variation in the erosion depth with "about 43.15%" is nonsense. "about" is correct, but there are at least two
significant decimals too many. Similar in lines 443/444

Line 371, "about 22%"

The author list of ref 29 needs to be expanded with respect to the authors' last names

ref. 41, use the regular mix of upper and lower case letters

Please insert blanks before references and brackets - they are not considered to be parts of the preceding words, but
their own entities.

The report is leaning towards text with little structure. I have no doubt that the authors have done their research competently,
but the presentation is rather tedious to read.

The language is largely acceptable, but the text ought to be edited by someone who is more fluent in spoken English.

Author Response

We have made changes and replied to your questions. Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

The publication of this manuscript in Coatings is proposed to be rejected on the basis of the following comments.

The first paragraph starts with a propaganda type military statement. The end of the second paragraph calls for “militarization”. Such statements are not acceptable in scientific journals.

As a matter of fact, every country and people on earth would like to have “development in peace” (see line 32).

From the scientific and technical point of views, the applied model is not realistic. In reality, the TiC component distribution is not atomistic with regular arrangement in such coatings, but its size and distribution strongly depend on the grain size of the TiC particles, not to mention the effect of dislocations.

The authors do not provide any comparison of their simulation’s results with experimental results. Therefore, the results of the simulation in this paper do not have significant meaning either from scientific or technical point of views.  

Author Response

We have made changes and replied to your questions. Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Review letter

Regarding the author’s revision, I am pleased to inform my satisfaction of present form of the manuscript entitled: “Research on the Ablation Resistance of TiC Particle Reinforced Aluminium-Based Composite Coatings on Armature Surface” for publication in Coatings.

Reviewer 3 Report

The authors have made all the necessary changes in their manuscript in order to fulfill the requirements of scientific publishing and the journal. Although, comparing with experimental results is still lacking, publication of this manuscript is recommended. Hopefully, relevant experimental results will be available soon.