Influence of Electron Beam Treatment on Structure and Phase Composition of TiB2–Ag Coating Deposited by Electrical Explosion Spraying
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe detail comment could be found in the attachment.
Comments for author File: 
Comments.pdf
Typos should be checked.
Author Response
1. Summary
I would like to express my sincere gratitude for reviewing our manuscript "Influence of electron beam treatment on structure and phase composition of TiB2-Ag coating deposited by electrical explosion spraying". Your feedback and insights have been invaluable in improving the quality of our work. Please find the detailed responses below and the corresponding revisions in the resubmitted files. All changes added according to your comments are marked in green.
2. Questions for General Evaluation
Does the introduction provide sufficient background and include all relevant references?
Response: More details were added to illustrate the state of the art in the electrical explosion spraying technique.
Are all the cited references relevant to the research?
Response: More cites were added to describe the state of the art in the electrical explosion spraying technique.
Are the methods adequately described?
Response: Methods were reworked according to comments.
Are the results clearly presented?
Response: Results were reworked according to comments.
Are the conclusions supported by the results?
Response: Conclusions were reworked according to comments.
3. Point-by-point response to Comments and Suggestions for Authors
Comments 1: More details should be added to illustrate the state of the art in this area.
Response 1: Thank you for pointing this out. We agree with this comment. This part of the manuscript was rewritten. The electrical explosion spraying process requires composite large-thickness conductors made of multiple foil layers and powder to produce composite coatings. Increasing the conductor's thickness leads to insufficient heating, non-synchronous explosion, and different-sized larger solid particles forming during the explosion [1], which directly causes unstable coating quality and structure. Electron beam treatment may be used to improve the surface and modified structure of the coating sprayed by electrical explosion.
1. Li, C.; Feng, J.; Yuan, W.; Cao, Y.; Han, R. Discharge Characteristics and Dynamic Process of Directional Spraying Binary and Ternary Alloy Coating via Electrical Explosion Method. In Proceedings of the Proceedings of the 4th International Symposium on Plasma and Energy Conversion; Dai, D., Zhang, C., Fang, Z., Lu, X., Eds.; Springer Nature: Singapore, 2023; pp. 302–311.
Comments 2: Where is the substrate? How did the author pre-treat it?
Response 2: Thank you for pointing this out. Before the electrical explosion spraying, the copper substrate was sanded with coarse sandpaper and gradually progressed to extremely fine sandpaper. Ultrasonic cleaning was used to remove residual particles. Treatment technique was added to the manuscript (lines 123 – 125).
Comments 3: Colud the author probide some pictures for evidence?
Response 3: Thank you for pointing this out. Unfortunately, we can’t provide any pictures due to filming was carried out during the study.
Comments 4: Closed diagram？
Response 4: Thank you for pointing this out. We suppose that those phases are substrate copper phases.
Comment 5: Should the bonding strength be evaluated?
Response 5: Thank you for pointing this out. During plasma exposure, the melting front propagated into the volume of the metal simultaneously with the radial spreading of plasma along the surface, which led to a flow of the upper layers of the melt. Kelvin-Helmholtz instability occurred because of the speed difference between the melted substrate and moving plasma. As a result, the fluid-mechanically mixed layer was formed on the boundary between coating and substrate after solidification, as shown in Figure 9 a. This layer may provide an important contribution to the adhesive bonding. However, it should be noted that Kelvin-Helmholtz instability may not occur in the peripheral parts of the coating or boundaries of the areas with droplet-like morphology, and fluid-mechanically mixed layers may not appear, either. As a result, the bond between coating and substrate may be weak in these areas.
Unfortunately, it is not possible to study coating adhesion now. However, this Research is planned for the future.
Comment 6: The porosities, the thermal conductivity and the electric conductivity should be tested.
Response 6: Thank you for pointing this out. We agree with this comment. However, we wanted to focus on structural and phase transformations. Thermal conductivity and electric conductivity will be tested in the future.
Commnet 7: The results should be discussed more systematically and deeply.
Response 7: Thank you for pointing this out. We agree with this comment. Conclusions were reworked. Results were discussed more systematically.
The irregular phase composition of the sprayed TiB2-Ag coating was significantly changed by the electron beam treatment. Ag, TiB2, B2O became the main phase in the modified coating. Increasing the pulse energy density and duration reduces the low-melting Ag phase and increases the mass fraction of the phases with high melted point B2O 164, TiB2 191. Regimes No.3 and No. 4 contributed to the formation of the copper-containing phases Cu 225, Cu2O 166 and Cu2Ti 63 due to the heating and melting of the copper substrate by the excess energy of the electron beam. The cross-sectional coating structure did not change significantly after electron beam treatment. There were silver matrix and TiB2 inclusions. The average TiB2 particle size decreased to 2.88 – 3.21 µm.
Reviewer 2 Report
Comments and Suggestions for AuthorsThis work reports on the preparation of TiB2/Ag coatings on Cu substrate. The influencing factors on the formation of coatings were discussed. The microstructure and phase composition of the prepared coatings were characterized. This work is original and can be accepted for publication after some revisions.
1) All XRD patterns should be treated. The background noise signals should be subtracted, and 2 theta degree stars from 25 to 140 .
2) For No 3 sample, why are there so many B-O oxides formed in the coating?
3) Is the bonding between coating and substrate strong? This part should be discussed.
Comments on the Quality of English LanguageMinor editing of English language required.
Author Response
1. Summary
I would like to express my sincere gratitude for reviewing our manuscript "Influence of electron beam treatment on structure and phase composition of TiB2-Ag coating deposited by electrical explosion spraying". Your feedback and insights have been invaluable in improving the quality of our work. Please find the detailed responses below and the corresponding revisions in the resubmitted files. All changes added according to your comments are marked in blue.
2. Questions for General Evaluation
Does the introduction provide sufficient background and include all relevant references?
Response: More details were added to illustrate the state of the art in the electrical explosion spraying technique.
Is the research design appropriate?
Are the methods adequately described?
Response: Some changes were added to Section 2 to clarify methods.
Are the results clearly presented?
Response: The results were reworked according to the comments.
Are the conclusions supported by the results?
3. Point-by-point response to Comments and Suggestions for Authors
Comments 1: All XRD patterns should be treated. The background noise signals should be subtracted, and 2 theta degree stars from 25 to 140.
Response 1: Thank you for pointing this out. We agree with this comment. All XDR patterns were reworked according to comment 1.
Comments 2: For No 3 sample, why are there so many B-O oxides formed in the coating?
Response 2: Thank you for pointing this out. TiB2 may decompose at temperatures over 2000 °C. [1] TiB2 undergoes thermal decomposition into Ti and B because the temperature exceeds 3000 °C during the electrical explosion spraying. B could be oxidized to Ð’2O3, Ð’2O because of the presence of air at 100 Pa in the discharge chamber.
1. Vlasova, M.; Kakazey, M.; Aguilar, P.A.M.; Tapia, R.G.; Reséndiz-González, M.C.; Hernandez, A.C.; Mel’nikov, I.V.; Fironov, Ya. TiN–TiB2 Сeramics Degradation in the Region of a Steady-State Laser Heating. Surface and Coatings Technology 2019, 378, 124738, doi:10.1016/j.surfcoat.2019.06.058.
Comments 3: Is the bonding between coating and substrate strong? This part should be discussed.
Response 3: Thank you for pointing this out. During plasma exposure, the melting front propagated into the volume of the metal simultaneously with the radial spreading of plasma along the surface, which led to a flow of the upper layers of the melt. Kelvin-Helmholtz instability occurred because of the speed difference between the melted substrate and moving plasma. As a result, the fluid-mechanically mixed layer was formed on the boundary between coating and substrate after solidification, as shown in Figure 9 a. This layer may provide an important contribution to the adhesive bonding. However, it should be noted that Kelvin-Helmholtz instability may not occur in the peripheral parts of the coating or boundaries of the areas with droplet-like morphology, and fluid-mechanically mixed layers may not appear, either. As a result, the bond between coating and substrate may be weak in these areas.
Unfortunately, it is not possible to study coating adhesion now. However, this Research is planned for the future.
Reviewer 3 Report
Comments and Suggestions for Authors1. Numbers used in the second paragraph of section 2 are not matching with numbers displayed in the schematic (Fig 1)
2. Line 117, “The TiB2 powder mass … ”, ‘2’ should be in the subscript.
3. What is “Solo” unit? Do you mean individual? Rephrase the sentence.
4. In table 1, numbers should be in the superscript (power) for the units (J/cm2, s-1)
5. Most of the places on the manuscript fractions are not represented correctly. Change numbers like “0,8” to “0.8”, this needs to be corrected at multiple places in the manuscript.
6. Legends are tiny in all figures; they must be enlarged for better readability.
7. Scale bars in SEM/EDS and TEM images are not visible.
8. Line 319, “The average TiB2 particle size 319 range decreased to 2,88 – 3,21 μm.” it must be grain size, generally particles are in the order of nm. Correct this everywhere.
9. Rephrase the following sentence “During the different 344 modes, the wary pulse energy density and duration are.” in the conclusion.
10. Line 121, use 'μ' in the following "pulse duration is 30-200 us "
Comments on the Quality of English Language
English needs to be improved.
Author Response
1. Summary
I would like to express my sincere gratitude for reviewing our manuscript "Influence of electron beam treatment on structure and phase composition of TiB2-Ag coating deposited by electrical explosion spraying". Your feedback and insights have been invaluable in improving the quality of our work. Please find the detailed responses below and the corresponding revisions in the resubmitted files. All changes added according to your comments are marked in yellow.
2. Questions for General Evaluation
Does the introduction provide sufficient background and include all relevant references?
Are all the cited references relevant to the research?
Is the research design appropriate?
Are the methods adequately described?
Are the results clearly presented?
Are the conclusions supported by the results?
3. Point-by-point response to Comments and Suggestions for Authors
Comments 1: Numbers used in the second paragraph of section 2 are not matching with numbers displayed in the schematic (Fig 1)
Response 1: Thank you for pointing this out. We agree with this comment. Therefore, we have changed the numbers in the second paragraph of section 2 according to the schematic (Fig 1).
Comments 2: Line 117, "The TiB2 powder mass...", 2' should be in the subscript.
Response 2: Thank you for pointing this out. We agree with this comment. Therefore, we have put 2' in the subscript.
Comments 3: What is "Solo" unit? Do you mean individual? Rephrase the sentence.
Response 3: Thank you for pointing this out. We agree with this comment. "Solo" is a device for electron beam treatment (pulse electron beam generator). The sentence was rephrased: "Prepared samples were treated by impulse electron beam by the pulse electron beam generator "SOLO"".
Comments 4: In table 1, numbers should be in the superscript (power) for the units (J/cm2, s-1)
Response 4: Thank you for pointing this out. We agree with this comment. Therefore, we have put (J/cm2, s-1) in the superscript.
Comments 5: Most of the places on the manuscript fractions are not represented correctly. Change numbers like "0,8" to "O.8", this needs to be corrected at multiple places in the manuscript.
Response 5: Thank you for pointing this out. We agree with this comment. Fractions were corrected.
Comments 6: Legends are tiny in all figures; they must be enlarged for better readability.
Response 6: Thank you for pointing this out. We agree with this comment. Figures 4 –10 and 12 – 16 were reworked. Legends were enlarged.
Comments 7: Scale bars in SEM/EDS and TEM images are not visible.
Response 7: Thank you for pointing this out. We agree with this comment. Figures 7, 10, 15, 16 were reworked. Bar captions were enlarged.
Comments 8: Line 319, "The average TiB2 particle size 319 range decreased to 2,88 - 3,21 um." it must be grain size, generally particles are in the order of nm. Correct this everywhere.
Response 8: Thank you for pointing this out. In the reviewed article, the particle size was mentioned. The particles in the coating are the non-melted TiB2 powder particles (~ 2–5 µm). We consider that µm is a more convenient unit to show particle size.
Comments 9: Rephrase the following sentence "During the different 344 modes, the wary pulse energy density and duration are." in the conclusion.
Response 9: Thank you for pointing this out. We agree with this comment. The sentence was rephrased: "The pulse energy density and duration varied during the different modes".
Comments 9: Line 121, use 'u' in the following "pulse duration is 30-200 us"
Response 10: Thank you for pointing this out. We agree with this comment. "us" was corrected to "µm".
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsI have no further comment.
Reviewer 2 Report
Comments and Suggestions for AuthorsMinor editing of English language required.
Comments on the Quality of English LanguageAll questions have been answered. I recommend it for publication.
