Enhancing the Corrosion Resistance of ZnAl-LDHs Films on AZ91D Magnesium Alloys by Designing Surface Roughness
Round 1
Reviewer 1 Report
Dear author(s), the manuscript titled ‘Enhancing the corrosion resistance of ZnAl-LDHs films on AZ91D magnesium alloys by designing surface roughness’, Manuscript ID: coatings-2276880, has some weaknesses that must be significantly improved before any further actions in the processing, if allowed by the Editor.
Please refer to the comments below:
1. Commenting on the ‘Abstract’ section, I would omit to introduce ‘rough’ results but, respectively, only a main, general conclusion at the end of this sentence. The rough results must be provided for the ‘Results and discussion’ section only.
2. According to the previous issue, one general conclusion indicating the novelty proposed should be addressed. Generally, this section must have some words on introduction, motivation, novelty and proposals. In the current form, it is not clear.
3. The is a lack of critical review of the current state of knowledge in the ‘Introduction’ section. Only a few words motivating the manuscript results presented are shown in lines 75-77. Please try to emphasize the meaning of the studies performed in the whole ‘Introduction’ section. Currently, its proposals do not derive from the literature review.
4. In section 2.2. there is only some general information on the surface analysis (measurement), especially for FE-SEM, 3D laser scanning microscope. Some details were presented for the XRD studies. Please provide some more sophisticated information on those analyses that, respectively, their accuracy has a significant influence on the results obtained.
5. Moreover, according to the previous suggestion, there are no details on all of the measurement precision. Please add some information, e.g. for profile measurement, about the measurement uncertainty, errors, and noise, like in:
(1) https://doi.org/10.1088/2051-672X/3/3/035004
(2) https://doi.org/10.24425/mms.2020.132772
(3) https://doi.org/10.24425/mms.2021.137706
This subsection must be significantly improved with valuable information that is crucial in surface investigation.
6. Some parameters from section 2, especially 2.2., look like are selected arbitrarily. Their values must be justified or, at least, referenced to the previous studies, if exist.
7. The font sizes in Figures 1 and 2 must be improved. It is difficult to read what are their values. Moreover, the whole quality of those figures must be enlarged. I suggest increasing the size of the figures or, respectively, dividing them into two separate ones with higher resolutions.
8. Similar to comment no.6, some values presented in section 3.5.1. are not justified, e.g. in lines 212-214.
9. In both subsections, 4.1 and 4.2, there is no critical view of the proposals presented. In fact, there is no critical discussion on the methods presented. The Author(s) concluded that the method is reliable and not presented its weaknesses.
10. Concluding with the above comments, there is no proposal for further studies, e.g.’ The outlook’. If the methods have no weaknesses or, respectively, there are non-resolved issues, wors looks like finished which I cannot agree.
11. The ‘Conclusion’ section must be significantly improved. In its current form is weak and does not respond to the significance of the studies presented in the paper. Firstly, it must be divided into separated and numbered gaps. Secondly, even one, the general proposal should be highlighted indicating the main goal improvement in the manuscript.
12. The full DOI links should be added to the references, if exist.
Generally, the proposed manuscript is interesting but, respectively, must be improved significantly which includes many weaknesses.
Some issues make understanding the paper difficult and the reader confused.
Therefore, the manuscript should be improved in a required manner before any further processing for publication in a quality journal as the Coatings is, if allowed by the Editor.
Author Response
Response to Reviewer 1 Comments
Point 1: Commenting on the ‘Abstract’ section, I would omit to introduce ‘rough’ results but, respectively, only a main, general conclusion at the end of this sentence. The rough results must be provided for the ‘Results and discussion’ section only.
Response 1: We unanimously agree with the reviewer’ opinions.We have revised the abstract and conclusions in accordance with the comments of the reviewers.
Point 2: According to the previous issue, one general conclusion indicating the novelty proposed should be addressed. Generally, this section must have some words on introduction, motivation, novelty and proposals. In the current form, it is not clear.
Response 2: We are embarrassed by the unclear description, so we have added some statements about introduction, motivation, novelty, and suggestions in this section.
Point 3: The is a lack of critical review of the current state of knowledge in the ‘Introduction’ section. Only a few words motivating the manuscript results presented are shown in lines 75-77. Please try to emphasize the meaning of the studies performed in the whole ‘Introduction’ section. Currently, its proposals do not derive from the literature review.
Response 3: I really admire the reviewer for his rigorous attitude. To solve this problem, we added a critical review of the current situation of knowledge in the "introduction" part, which was marked in red in the original text.
Point 4: In section 2.2. there is only some general information on the surface analysis (measurement), especially for FE-SEM, 3D laser scanning microscope. Some details were presented for the XRD studies. Please provide some more sophisticated information on those analyses that, respectively, their accuracy has a significant influence on the results obtained.
Response 4: We have re-written this part according to the judge's suggestion, and added relevant detailed setting parameters.
Point 5:Moreover, according to the previous suggestion, there are no details on all of the measurement precision. Please add some information, e.g. for profile measurement, about the measurement uncertainty, errors, and noise, like in:
(1) https://doi.org/10.1088/2051-672X/3/3/035004
(2) https://doi.org/10.24425/mms.2020.132772
(3) https://doi.org/10.24425/mms.2021.137706
This subsection must be significantly improved with valuable information that is crucial in surface investigation.
Response 5: Thank you very much for the reference materials provided by the reviewer. After careful reading, some precision details of contour measurement were added to the original manuscript.
Point 6: Some parameters from section 2, especially 2.2., look like are selected arbitrarily. Their values must be justified or, at least, referenced to the previous studies, if exist.
Response 6: We have re-written this part according to the judge's suggestion, and added relevant detailed setting parameters.
Point 7: The font sizes in Figures 1 and 2 must be improved. It is difficult to read what are their values. Moreover, the whole quality of those figures must be enlarged. I suggest increasing the size of the figures or, respectively, dividing them into two separate ones with higher resolutions.
Response 7: We are very sorry for our careless writing and have increased the size of Figure 1 and Figure 2, as well as the font size, so that reviewers can clearly see the values in the figure.
Point 8: Similar to comment no.6, some values presented in section 3.5.1. are not justified, e.g. in lines 212-214.
Response 8: We thank the reviewer for asking this question. In addition, some values proposed in Section 3.5.1 were refitted and corrected. The concentration of NaCl in lines 212-214 of the original manuscript was carefully verified and repeated experiments were carried out. Finally, "3.5wt%" should be corrected to "0.1M".
Point 9: In both subsections, 4.1 and 4.2, there is no critical view of the proposals presented. In fact, there is no critical discussion on the methods presented. The Author(s) concluded that the method is reliable and not presented its weaknesses.
Response 9: Based on the comments of the reviewers, the reliability and weaknesses of the methods in the study were explained and discussed.
Point 10: Concluding with the above comments, there is no proposal for further studies, e.g.’ The outlook’. If the methods have no weaknesses or, respectively, there are non-resolved issues, wors looks like finished which I cannot agree.
Response 10: We think this is an excellent suggestion. It is indeed unreasonable that no further research is proposed in the original draft, so we have added further research questions at the end of Section 4.2.
Point 11: The ‘Conclusion’ section must be significantly improved. In its current form is weak and does not respond to the significance of the studies presented in the paper. Firstly, it must be divided into separated and numbered gaps. Secondly, even one, the general proposal should be highlighted indicating the main goal improvement in the manuscript.
Response 11: According to the Reviewer’s comment, three main conclusions have been drawn after refining and summarizing the content of this paper.
Point 12: The full DOI links should be added to the references, if exist.
Response 12: We are very sorry for the irregular writing.Full DOI links have been added to each reference and highlighted in red.
Reviewer 2 Report
The article concerns an interesting issue taking into account an effect of surface roughness on the corrosion resistance of AZ91D magnesium alloy with ZnAl-LDHs films. This work is of interest in the field of corrosion resistance of Mg-based alloys, but it has a number of questions that arise after reading the article.
1. The article needs a little text editing.
2. What is the novelty of the proposed study?
3. Please improve Figure 1 – axis labels are not visible.
4. Why Authors did not considered the coating adhesion? It is important property.
5. Statistical analysis for the corrosion parameters obtained from Tafel extrapolation of polarization curves would be of helpful.
6. First the reference to Figures and Tables should be added in the text, and then Figures/Tables should be placed.
7. The discussion section is too general. Please improve it.
8. Please, improve references 21, 26.
Author Response
Response to Reviewer 2 Comments
Point 1: The article needs a little text editing.
Response 1: We unanimously agree with the reviewer’ opinions.We tried our best to improve the manuscript and made some changes to the manuscript. These changes will not influence the content and framework of the paper. And here we did not list the changes but marked in red in the revised paper. We appreciate for Reviewers’warm work earnestly and hope that the correction will meet with approval.
Point 2: What is the novelty of the proposed study?
Response 2: We consider that surface roughness is an important surface characteristic of ZnAl-LDHs films. The surface roughness of the film is closely related to the surface machining state of the substrate. The innovation of this paper is to discuss the influence of matrix processing parameters on film growth and corrosion resistance.
Point 3: Please improve Figure 1 – axis labels are not visible
Response 3: We are very sorry for our careless writing. We have improved Figure 1 – axis labels.
Point 4: Why Authors did not considered the coating adhesion? It is important property..
Response 4: According to the Reviewer’s comment, we have added experimental data on evaluating film adhesion.
Point 5: Statistical analysis for the corrosion parameters obtained from Tafel extrapolation of polarization curves would be of helpful.
Response 5: We strongly agree with the reviewers' opinions and have added the corrosion potential and corrosion current density obtained from Tafel extrapolation of polarization curves in our paper.
Point 6: First the reference to Figures and Tables should be added in the text, and then Figures/Tables should be placed.
Response 6: We think this is an excellent suggestion., but we have doubts. We do not know exactly what part of the article is. Please specify it in detail in the next revision. We will seriously revise it and express our sincere gratitude!
Point 7: The discussion section is too general. Please improve it.
Response 7: We sincerely thank the reviewer for careful reading and have made every effort to revise the discussion section.
Point 8: Please, improve references 21, 26.
Response 8: We are very sorry for our incorrect writing. We have revised the format of the references 21, 26.
Reviewer 3 Report
1. English is not satisfactory.
2. The colours in figure 5 are not clearly distinguishable.
3. The surface polishing with different grade emery papers will result in different roughness, which could affect the formation of LDHs. Still, how the authors can conclude that the improved corrosion resistance is due to the better LDHs film formed. Authors shall produce PDP plots of the four samples after polishing, but without LDH coating. The data can be added as supporting information.
4. Anti-corrosion mechanism shall be modified. It needs to be clearly written. A recent book on the mentioned topic is available https://doi.org/10.1007/978-3-030-89976-9
5. Contact Angles shall be measured for bare and LDHs coated samples.
Author Response
Response to Reviewer 3 Comments
Point 1: English is not satisfactory.
Response 1: We unanimously agree with the reviewer’ opinions.We tried our best to improve the manuscript and made some changes to the manuscript. These changes will not influence the content and framework of the paper. And here we did not list the changes but marked in red in the revised paper. We appreciate for Reviewers’warm work earnestly and hope that the correction will meet with approval.
Point 2: The colours in figure 5 are not clearly distinguishable.
Response 2: According to the reviewer's comments, we have carefully modified the colours in Figure 7 (Figure 5 in the original manuscript).
Point 3: The surface polishing with different grade emery papers will result in different roughness, which could affect the formation of LDHs. Still, how the authors can conclude that the improved corrosion resistance is due to the better LDHs film formed. Authors shall produce PDP plots of the four samples after polishing, but without LDH coating. The data can be added as supporting information.
Response 3: We agree that more studies would be useful to understand the details. In order to conclude that better corrosion resistance was achieved due to the formation of a better LDHs film. We showed a comparison between two types of samples in Figure 7. One was the comparison of corrosion resistance of samples with the same roughness, with and without LDHs film; The second was to compare the corrosion resistance of samples with different roughness and uniformly coated ZnAl-LDHs thin films. We believe that this conclusion can be preliminarily seen by comparing the two samples of the second type. If the reviewer truly believes that this approach is not entirely reasonable, we can add another experiment at the next revision.
Point 4: Anti-corrosion mechanism shall be modified. It needs to be clearly written. A recent book on the mentioned topic is available https://doi.org/10.1007/978-3-030-89976-9
Response 4: We feel great thanks for your professional review work on our article. According to Chapter 5 of the book, we have modified the preservative mechanism.
Point 5: Contact Angles shall be measured for bare and LDHs coated samples.
Response 5: We think this is an excellent suggestion. We have measured the contact angle between the bare sample and the LDHs coating sample to characterize the effect of surface roughness on the wettability of the samples, as shown in Figure 5.
Round 2
Reviewer 1 Report
Dear Author(s), the manuscript ‘Enhancing the corrosion resistance of ZnAl-LDHs films on AZ91D magnesium alloys by designing surface roughness’, Manuscript ID: coatings-2276880, has been improved enough to be further processed so, respectively, can be considered for publication by the quality journal as the Coatings is.
Author Response
Response to Reviewer 1 Comments
Point 1: Dear Author(s), the manuscript ‘Enhancing the corrosion resistance of ZnAl-LDHs films on AZ91D magnesium alloys by designing surface roughness’, Manuscript ID: coatings-2276880, has been improved enough to be further processed so, respectively, can be considered for publication by the quality journal as the Coatings is.
Response 1: Thank you very much for your recognition of the quality of our article. We have made further revisions to improve the article.
Reviewer 3 Report
The authors responded (Response 4) that According to Chapter 5 of the book (978-3-030-89976-9), we have modified the preservative mechanism. If the author used the book's information, the book shall be cited and added to the cited references.
Author Response
Response to Reviewer 3 Comments
Point 1: The authors responded (Response 4) that According to Chapter 5 of the book (978-3-030-89976-9), we have modified the preservative mechanism. If the author used the book's information, the book shall be cited and added to the cited references.
Response 1: We are embarrassed that reference book has not been added to the references. In the revised version we have added and numbered it [31].
