Effects of Si Content on the Growth of Oxide Layers in Carbon Steels during the Heating Process

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Review comments are attached

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Improvement of linguistics is imperative

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The presented manuscript describes the research carried out in a very popular direction in the industry and examines important aspects of the formation of the oxide layer on the surface of hot-rolled iron. The conclusions are sufficiently substantiated and supported by the results obtained. At the same time, there are several comments that I must pay attention to. Correction of these shortcomings, in my opinion, is necessary before the publication of the manuscript considered.

- Line 131-133 - It seems that there are problems with formatting the text - a very strange combination of punctuation

- Line 141-143 "Study on the oxidation kinetics of iron oxide: The experiment was carried. Study on the oxidation kinetics of iron oxide: The experiment was carried out in a controlled resistance heating furnace (HT1350 type, Longkou Electric Furnace Factory)." The same as above. What do you mean saying "The experiment was carried"? This part of text should be reformated.

- Figure 2 shows nothing. I can not see any difference because (a) and (b) shows sample at different scales and both picture are of poor qualuty. The quality of photo must be improoved

- Line 218 - problems with punctuation between iron oxides

- Figure 7, Figure 8 and Table 2 must be reconsidered. The data presented did not show error bars and therefore the oxide layer thikness for 0.04Si at 800C is higher than that one for 900C - this is impossible. So, you must show averaging error for the value of the oxide layer thickness at each temperature point for each sample. 

- Why is the A1 and A5 pair used in the model? In the presented expression (1), they are not independent, which redefines the system. It is necessary to exclude A5 and re-conduct the regression analysis taking into account the errors. I am sure that after such actions there will not be an abnormally high calculated value of the layer thickness for the sample of 0.90Si at low temperatures

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The revised version of the manuscript is considerably improved.  The authors reponded to the comments made and proceeded with revisions.

One comment concerns the revision of the statement "High temperature heating promotes the diffusion reaction of Fe and O atoms, Fe from the steel plate matrix and O from the air, at high temperatures to generate an oxide layer, the reaction process is Fe + O →FeO / Fe₂O₃ / Fe₃O₄， thus creating conditions for the formation of the oxidized layer [13].".  The revised verison is worse than before.  It should be corrected to read "High temperature heating promotes the diffusion reaction of Fe and O atoms, i.e. Fe from the steel plate matrix and O from the air, at high temperatures generate an oxide layer, with the reaction process described as Fe + O →FeO / Fe₂O₃ / Fe₃O₄， thus creating conditions for the formation of the oxidized layer [13].". 

The manuscript could then be considered.

Comments on the Quality of English Language

Review comments are provided above

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Changes have indeed been made in the manuscript after the review, it can be seen. However, for some reason, the illustrations of calculations of the thickness of the oxide layer have been removed. Using the data presented in Table 2, I made a calculation of the graphs and realized that absolutely no changes were made in the calculations relative to the original version and the errors of determination were not taken into account. It can only be seen that the errors were used to construct Figure 7, in which a strong correction of the data is noticeable (data manipulation?). For a sample of 0.90 Si, the calculated layer thickness is still 55 microns at temperatures up to 600 C. I strongly ask you to take this remark into account.

Author Response

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Author Response File: Author Response.pdf

Round 3

Reviewer 2 Report

Comments and Suggestions for Authors

The authors took into account the previously mentioned comments. As presented, the manuscript can be recommended for publication.

For the future, I would recommend considering another approximation model that will more correctly describe the existence of several key points of growth in the thickness of the oxide layer, as observed experimentally and described in the text. The model used is of limited practical use