Wear and Corrosion Resistance of Chromium–Vanadium Carbide Coatings Produced via Thermo-Reactive Deposition
Round 1
Reviewer 1 Report
Review on Manuscript ID Coatings-456403
Title: "Wear and corrosion resistance of chromium-vanadium carbide coatings produced through TRD", authors: Fabio Castillejo, J.J. Olaya* and J.E. Alfonso.
The authors study the physical properties of V/Cr carbides coated and uncoated AISI D2 steel, and corrosion processes of these in a corrosive media represented by a sodium chloride solution.
This work is supported by experimental results but the authors do not discuss the obtained results and do not compare their data with literature. The paper can be published after MAJOR revision.
The main revisions that I consider to be made are listed below:
line 80 – Table 1
M1 = (Wt%Na2B4O7)+(Wt%Fe-Cr)+(Wt%Fe-V)+(Wt%Al) = 73+15+8+3 = 99 %
M2 = (Wt%Na2B4O7)+(Wt%Fe-Cr)+(Wt%Fe-V)+(Wt%Al) = 81+26+5+3 = 115 %
M3 = (Wt%Na2B4O7)+(Wt%Fe-Cr)+(Wt%Fe-V)+(Wt%Al) = 67+30+0+3 = 100 %
M1 = (Wt%Na2B4O7)+(Wt%Fe-Cr)+(Wt%Fe-V)+(Wt%Al) = 81+0+16+3 = 100 %
The authors need to reconsider the compositions of baths M1 and M2.
line 128 – Figure 2
The authors must add the micrograph corresponding to the M1 sample.
lines from 137 to 139
Figure 4 is NOT discussed at all. Authors must comment on the data obtained not only provide graphics.
line 140 – Figure 3
Figure 3 is not clear. It needs to be changed.
line 143 – Figure 4
The authors must add the XRD patterns corresponding to the M3 and M4 samples.
line 145
Figure 5 is NOT discussed at all. Authors must comment on the data obtained not only provide graphics.
line 151 – Figure 5
Figure 5 is not clear. It needs to be changed.
line 151 – Figure 5b
The synthesis bath for M1 sample contains 15% Fe-Cr and 8% Fe-V, and the EDS spectrum 5b indicates a higher concentration of Vanadium compared to Chromium. Why? Authors must comment on the data obtained not only provide graphics.
line 141 / line 143 / line 151 / line 175 (Figures 3, 4, 5 and 6)
Why B and Na elements are not identified in these spectra? They are the major components of baths. The authors have to give more comments, not just the convenient ones!
line 167
The authors identify in the spectrum 6d the adsorbed water. Knowing that working at a temperature of 1020 °C, the authors have to justify the presence of water. Which is the time from the synthesis of carbides to their analysis? What are the conditions in which these carbides were kept?
line 177 - Figure 6
The authors should perform a comparison of XPS spectra for all samples not only for the M2 sample. Otherwise, it should be justified why only the XPS spectrum of the M2 sample was given. The experimental results do not indicate the M2 sample as being the most effective.
line 188
Figure 8 is NOT discussed at all. Authors must comment on the data obtained not only provide graphics.
line 198
The authors must add the SEM micrographs corresponding to the M3 and M4 samples.
line 201
If the authors made the Tafel polarizations, it would be useful for readers to compare them.
line 217
The unit of measurement for the anode and cathode Tafel slopes should be specified.
line 217 - Table 3
The Ecorr value for M3 must be negative???
line 240
The authors need to provide more detailed comments on EIS analysis results.
The work is unkempt, it seems to be in a hurry, there are several errors that need to be revised. Coatings journal require a specific format of references, authors must pay more attention in their writing. There are many grammar and typing mistakes. The authors must revise the entire manuscript.
Author Response
line 80 – Table 1
M1 = (Wt%Na2B4O7)+(Wt%Fe-Cr)+(Wt%Fe-V)+(Wt%Al) = 73+15+8+3 = 99 %
M2 = (Wt%Na2B4O7)+(Wt%Fe-Cr)+(Wt%Fe-V)+(Wt%Al) = 81+26+5+3 = 115 %
M3 = (Wt%Na2B4O7)+(Wt%Fe-Cr)+(Wt%Fe-V)+(Wt%Al) = 67+30+0+3 = 100 %
M1 = (Wt%Na2B4O7)+(Wt%Fe-Cr)+(Wt%Fe-V)+(Wt%Al) = 81+0+16+3 = 100 %
The authors need to reconsider the compositions of baths M1 and M2.
Response. the data was corrected
line 128 – Figure 2
The authors must add the micrograph corresponding to the M1 sample.
Response. The figure M1 was added.
lines from 137 to 139
Figure 4 is NOT discussed at all. Authors must comment on the data obtained not only provide graphics.
Response. We improve the discussion here. In the text was included the following paragraph:
Due the complex structure of the XRD patterns of the M1 and M2 samples, in figure 4 in detail the deconvolution of these patterns, where we see the presence of two chromium carbides and a vanadium carbide. These results suggest that the samples with major content the Fe-Cr allows the chemical reaction between carbon of the steel and the chromium of the bath. The presence of vanadium carbide in the M1 and M2 samples in the coatings can be explained by the greater thermodynamic stability in forming vanadium carbide, because the energy of formation of vanadium carbide (-24 Kcal / mol) [19] is less than that of the formation of chromium carbide (-18 Kcal/mol) [20].
line 140 – Figure 3
Figure 3 is not clear. It needs to be changed.
Response. The figure 3 was improved.
line 143 – Figure 4
The authors must add the XRD patterns corresponding to the M3 and M4 samples.
Response. The XRD patterns of M3 and M3 was added.
line 145
Figure 5 is NOT discussed at all. Authors must comment on the data obtained not only provide graphics.
Response. We improve the discussion here. In the text was included the following paragraph:
Figure 5 shows Ka and Kb emission lines of the chromium (5.41and 5.95 keV), vanadium (4.95 and 5.43keV), aluminum (1.48 and 1.56keV) and iron (6.40 and 7.06 keV) in the coatings; the lines of the and B not are detectable by EDS technique due energies of lines are about of the 0.185 keV. Table 2 summarize the content of each element in at%. These results allow established that the M1 sample even though sinterized with major ferro-chromium content with respect to ferro-vanadium, have more V that Cr in the coating, this due to that the formation energy of the vanadium carbide is more negative than chromium carbide. In the M2 and M3 sample, the percentage of Cr increase because the ferro-chromium increase from 26 % to 30 % wt. Finally, the M4 sample have high content of vanadium because to the lack of ferro-chromium in the fabrication process.
line 151 – Figure 5
Figure 5 is not clear. It needs to be changed.
Response. The Figure 5 was improved.
line 151 – Figure 5b
The synthesis bath for M1 sample contains 15% Fe-Cr and 8% Fe-V, and the EDS spectrum 5b indicates a higher concentration of Vanadium compared to Chromium. Why? Authors must comment on the data obtained not only provide graphics.
Response. Response. We include the table 2, related with the chemical composition of the carbides grown on D2 steel evaluated by EDS and it was explained in the text.
line 141 / line 143 / line 151 / line 175 (Figures 3, 4, 5 and 6)
Why B and Na elements are not identified in these spectra? They are the major components of baths. The authors have to give more comments, not just the convenient ones!
Response. The Kα line of B has an energy of the 0.185 keV. This energy is not enough to be detected by our EDS probe. Additionally the Na don't react with the elements that produce the coating. The Na only is in the bath.
line 167
The authors identify in the spectrum 6d the adsorbed water. Knowing that working at a temperature of 1020 °C, the authors have to justify the presence of water. Which is the time from the synthesis of carbides to their analysis? What are the conditions in which these carbides were kept?
Response. The XPS signal of water appears when de sample is exposed at the atmosphere. We include this in the text.
line 177 - Figure 6
The authors should perform a comparison of XPS spectra for all samples not only for the M2 sample. Otherwise, it should be justified why only the XPS spectrum of the M2 sample was given. The experimental results do not indicate the M2 sample as being the most effective.
Response. XPS analysis was made with a scientific collaboration but unfortunately just was made in M2 sample, than allow to study the chemical composition in the surface. However, the EDS analysis was include for all samples in order to study the chemical composition..
line 188
Figure 8 is NOT discussed at all. Authors must comment on the data obtained not only provide graphics.
Response. We improve the discussion here. In the text was included the following paragraph:
Figure 8 shows the scar wear for the M1 and M2 samples. The figure shows parallel lines or channels, characteristic of adhesive wear. According to Adachi and Hutchings, this situation is known as grooving wear, or abrasion of two bodies [27]. These slots arise from the cutting action of abrasive microparticles that are fundamentally embedded in the ball with which the test is conducted. The microparticles were produced possibly by mechanisms of contact fatigue and plastic deformation that is generated during the contact of the tribological pair. These types of wear can be combined with an oxidation wear mechanism promoted by the formation of oxides due to the increase in temperature and the reaction of elements such as chromium and vanadium with the oxygen of the environment, forming a possible film that prevented continuous removal of material.
line 198
The authors must add the SEM micrographs corresponding to the M3 and M4 samples.
Response. These micrographs were added.
line 201
If the authors made the Tafel polarizations, it would be useful for readers to compare them.
Response. The discussion of Tafel polarizations was complement with the EIS test
line 217
The unit of measurement for the anode and cathode Tafel slopes should be specified.
Response. The Tafel slopes were added.
line 217 - Table 3
The Ecorr value for M3 must be negative???
Response. We made the correction, the Ecorr value is negative.
line 240
The authors need to provide more detailed comments on EIS analysis results.
Response. We improve the discussion here. In include the table 5. In the text was included the following paragraph: The values of the parameters obtained after fitting of the equivalent circuits proposed are summarized in table 5 for the coatings produced, after exposure times of 168 h. The result evidence that Rpor and Rcor is minor for M4 sample, indicating low corrosion resistance for this coating. This could be explained by only formation of vanadium oxide in the coating during its production as observed in the XPS spectra. Whereas in the coatings with high content of chromium have higher values of Rcor and Rpor which could be explained by the presence of Cr23C6 and Cr7C3 along with the formation of the stable oxide Cr2O3 surely creating a passive layer on the coating that protects the substrate from electrolyte penetration.
Reviewer 2 Report
This paper examined the wear behaviour and corrosion properties of chromium-vanadium carbide coatings produced by thermo-reactive deposition. This paper presents new results about deposition chromium-vanadium carbide coatings by thermo-reactive deposition. So, I believe it's an article to be published in the Coatings. However, I have some minor remarks:
1. The title of the paper should not be written in abbreviation, i.e. “TRD” should be “thermo-reactive deposition”.
2. The label in XRD graph is not clear, XRD peak indexing is unreadable.
2. The hardness values for M3 and M4 samples in Table 2 shouldn’t be comma. The same applies to the parameters obtained from the linear polarization curves in Table 3.
3. The wear scar of the alumina ball is important and it is suggested to include in the results and discussion.
4. It is mandatory that the experimental detail states whether the EIS spectra were measured at the open circuit potential or not.
Author Response
The title of the paper should not be written in abbreviation, i.e. “TRD” should be “thermo-reactive deposition”.
Response. The title was improved.
2. The label in XRD graph is not clear, XRD peak indexing is unreadable.
Response. The label in XRD graph was improved.
2. The hardness values for M3 and M4 samples in Table 2 shouldn’t be comma. The same applies to the parameters obtained from the linear polarization curves in Table 3.
Response. the comma was changed by point.
3. The wear scar of the alumina ball is important and it is suggested to include in the results and discussion.
Response. We added the wear rate for all samples.
4. It is mandatory that the experimental detail states whether the EIS spectra were measured at the open circuit potential or not.
Response. We added the values of the parameters obtained after fitting of the equivalent circuits proposed to the coatings produced
Reviewer 3 Report
The preseted work involve the characterization of TRD coatings on steels. The work is interesting but some major corrections have to be performed before publication:
1)The authors should state clearly the objective of the work
2) In the introduction part a comparison with the litarature on TRD coatings have to be performed and the novelty in comparison with the litarature have to be explained
3) The paper is only a description of the characterization of the different samples. Scintific discuscussion is required trying to explain the different behaviour of the samples
4) FIg.3 is not clear and not acceptable in term of quality. The labels have to be clear and readable
Author Response
1)The authors should state clearly the objective of the work
The objetive was added in the last part of the introduction.
Therefore, the objective of this paper is deposit chromium-vanadium carbide coatings on D2 steel substrates using the TRD technique for achieve high performance in tribological and electrochemical applications. The coatings produced will be characterize and compared with the performance of binary carbides with respect to their wear and corrosion resistance.
2) In the introduction part a comparison with the litarature on TRD coatings have to be performed and the novelty in comparison with the litarature have to be explained
Response. We improve the redaction in the introduction, and we highlight the novelty the work. This coating have not produced before.
3) The paper is only a description of the characterization of the different samples. Scintific discuscussion is required trying to explain the different behaviour of the samples.
Response. The results were widely discussed along of the paper.
4) FIg.3 is not clear and not acceptable in term of quality. The labels have to be clear and readable
Response. The figure was improved.
Round 2
Reviewer 1 Report
Review on Manuscript ID Coatings-456403
Title: "Wear and corrosion resistance of chromium-vanadium carbide coatings produced through TRD", authors: Fabio Castillejo, J.J. Olaya* and J.E. Alfonso.
The authors study the physical properties of V/Cr carbides coated and uncoated AISI D2 steel, and corrosion processes of these in a corrosive media represented by a sodium chloride solution.
The paper can be published after MINOR revision.
The main revisions that I consider to be made are listed below:
line 155 – Figure 4
The authors must add the XRD patterns corresponding to the M3 and M4 samples.
line 225 – Figure 8
The authors must add the SEM micrographs corresponding to the M3 and M4 samples.
line 228
The authors show the polarization curves but do not show the Tafel polarizations. If the authors made the Tafel polarizations, it would be useful for readers to see them.
line 244
The unit of measurement for the anode and cathode Tafel slopes should be specified.
Coatings journal require a specific format of references, authors must pay more attention in their writing. There are many grammar and typing mistakes. The authors must revise the entire manuscript.
Author Response
The Tafel slope units were include.
The references were written in the format of journal Coatings
The manuscript was revised by a native english .
Reviewer 2 Report
In Table 3, the wear rate of the carbide coatings is higher than the wear rate of substrate, which is opposed to what authors written in the text. Please refer to line 192 to 194.
Author Response
The wear rate was corrected of the substrate.
Reviewer 3 Report
Considering the authors answered to all the issues i suggest for the manuscript publication in the present form
Author Response
OK
