Electroless Ni–P Plating on Mullite Powders and Study of the Mechanical Properties of Its Plasma-Sprayed Coating
Round 1
Reviewer 1 Report
Dear authors,
See my comments
Comments for author File: 
Comments.pdf
Author Response
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Author Response File: Author Response.pdf
Reviewer 2 Report
In this work, the authors plated the mullite particles with Ni-P and characterized the coating using different techniques. Then they used these plated particles to coat a substrate and compared the mechanical properties and the effect of thermal cycling. A significant improvement of attributes in improved coating technology was achieved.
The work presented here is impressive. It is very well structured and very well presented. The language is very clear, simple, and understandable. It was a pleasure reading and reviewing this article. You did a fantastic job here. I have a few following suggestions that would help in further improving the quality of the presentation and will help future readers in following the work more enjoyably:
1- Please use third person passive tense throughout the document, which means instead of using we, I, us, state "the work was carried out….."
2- The text style at some positions in the document is different. Would you please check with that? while revising the document, please make sure that you follow the journal author guidelines strictly
3- I feel that almost all the figures in the document can be significantly improved two enhance the reader's experience. Please see the attached annotated PDF file for detailed comments on each figure; it contains my suggestions for improving these figures.
4- please highlight the optimal design factor in Table 2
5- the research methodology is very well scripted in section two of the article. It would be awesome if the authors could also provide a flow chart containing all the steps, their respective inputs, and their respective outputs, how the information and samples passed from one stage to another. At the beginning or end of the methodology section, this flow chart will help summarize the whole methodology and further enhance the reader's experience.
6- page for lines 133 to 141, is my getting microhardness the correct way of doing this, what was the average particle size if it is too small then instead of measuring the microhardness using this kind of methodology, the user would be measuring the hardness of particle as well as substrate, and that will affect the results. would you please justify your selection of measurement methodology
7- this small equation 1 can be directly put in the paragraph rather than placed separately below a paragraph
8- page 5, lines 155 to 158, qualitative and subjective observations, which I feel are relatively oversimplified and overly stated. Would you please change the language adequately
9- figure 2C and figure 3A are the same. Can the author somehow find a way to avoid the repetition of this figure? my suggestion would be to merge figure two and figure 3
10- it seems that the sample for the cross-sectional area, shown in figure 3B, was not very well prepared. Why are there situations and the quality of the figure is not very good?
11- the authors have mentioned that the thickness of the layer is approximately 2 micrometers. How was this thickness measured? What are the tolerances?
12- it would be great if Figure 4 and figure seven could be constructed by pointing out the critical peaks which are discussed in the subsequent sections
- I don't understand how these XRD lines come on top of each other on the intensity scale if the scale is not restarting from zero. it would be great if you could please provide a graduated intensity scale and justify the movement of graphs upwards
13- please move figure 5 to its subsequent section. I like the construction of this figure where the authors tried to show what the corresponding peak relates to
14- figure six can also be significantly improved. Please see the annotated PDF file for further comments
15- I suggest that instead of using terms coating 1 and 2, use appropriate short names for each sample throughout the document. This will help readers follow up more quickly and attach their imagination to what the authors have tried to show here.
16- add percentage difference of each attribute in an extra column below table 4
17- in Section 3.5, Some information about residual stress accumulation in steel due to thermal cycling is missing. Please use the following documents as sources and add this information adequately in this section:
- DOI:10.5545/SV-jme.2019.6073
https://doi.org/10.1016/j.dt.2020.09.005
This is excellent work indeed, and I hope that my comments will help you further improve its outlook and will be helpful in further improving the reader's experience. Also, please prepare an adequate graphical abstract and submit that with the revised document. These small but essential points will hopefully help bring this work to the limelight.
I wish you all the best:
Comments for author File: Comments.pdf
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
In the article “Electroless Ni–P plating on mullite powders and study of the mechanical properties of its plasma-sprayed coating” the Ni–P layer on the surface of the mullite powder by electroless plating was obtained and plasma-sprayed coating on a 304 stainless steel was fabricated. The authors tried to reveal and describe the growth mechanism of the Ni–P layer during the plating. The theme of the article is very interesting and relevant. But, a few comments should be providing.
- The mechanism of the Ni–P layer formation on mullite powders is not clear enough. What the chemical reactions are occurred during this process? The scheme of the mullite powders pretreatment is presented. But, the scheme of the growth mechanism of the Ni–P layer should be provided additionally.
- Very high carbon content 22.61 at.% is detected on the surface of the Ni–P/mullite composite powder by the EDS analysis (Fig. 3c). How do the authors explain this phenomenon? It cannot be just contamination.
- The phases of mullite, Ni3P and Ni were revealed in the Ni–P/mullite composite powder by XRD. The XPS spectrum shows that the surface of the coated powder layer is composed mainly of Ni3(PO4)2, Ni(OH)2, Ni and P. What is the exact phase composition of this material?
- The elemental composition of the plasma-sprayed coating does not provided in this work. XRD analyzes are not enough in this case, since the coating contains an amorphous phase.
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Well-done
