The Effect of the Dilution Level on Microstructure and Wear Resistance of Fe-Cr-CV Hardfacing Coatings Deposited by PTA-P
Round 1
Reviewer 1 Report
The effect of dilution on wear resistance in PTA coating deposition was studied in this manuscript. The wear resistance under different load conditions is demonstrated. The hardness of coatings is measured. The work is interesting and important. But some issues are not very clear. And it is suggested to add some points.
However, there are some points to be discussed.
(1) The phase of the deposition is suggested to be added. In order to know the microstructure, XRD test is suggested to do.
(2) Metallographic structure is suggested to be added and analyzed.
(3) The abrasion resistance of coatings is higher than that of substrates in the manuscript. The reason is not discussed sufficiently.
(4) In materials and methods part, the temperature between the before bead and the after bead is controlled lower than 40 ℃. Why this temperature is chosed?
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
One of the ways to solve the wear problems is associated with the formation of layers on the surface of parts, the level of operational properties of which is significantly exceeds the properties of the base material. Application of functional protective layers on machine parts allows you to increase the level of reliability and durability products operating in extreme conditions of abrasive wear. The ability to protect used parts, as well as restore the geometry of worn surfaces, greatly reduces the economic losses caused by decommissioning and the need for subsequent replacement of equipment. Therefore, the article is very relevant, and its results are useful for science and practice. At the same time, there are a number of questions:
1. The article measured the hardness of the coatings deposited on base material. At the same time, it would be useful to show the change in hardness (and microhardness) values from the surface of the deposited layer, through the fusion zone and further into the base material. This would show the property changes, their gradient.
2. It is not clear from the article whether the formation of a uniform compositional structure of the Fe-Cr-C-V coating is ensured?
3. It was good to formulate regression dependencies connecting the main surfacing mode parameters (arc current value, surfacing speed, powder feed rate) with microstructural characteristics of the carbide subsystem of Fe-Cr-C-V coatings.
4. Difference in the sizes of the image in fig. 6, 8, 9, 10 worsens the appearance of the article. I think it would have been worth taking images at 2 times more than now, magnification for SEM images from figures 6 and 10. This would save the authors from having to stretch them to fit the width of the page.
5. Formulas (1-3) was not written in the by special redactor, but simply in text. Worth fixing it. Now equations are appearance is unsatisfactory.
6. It is known that the reheating zones (roller overlaps) differ in the structure of the sections. The authors do not study them. Why?
7. It is known that the hardness of composite coatings is determined both by the phase composition of the matrix and by the volume fraction of inclusions strengthening it. At numerous papers has shown that with an increase in the volumetric amount of carbide phases, the hardness also increases. Perhaps it was worthwhile to study in more detail the relationship between hardness and the volume fraction of martensite in the matrix coatings and the total volume fraction of carbide phases?
8. It would be useful to show the morphology of the cladding surface after wear, an example of such an analysis is given in: https://sciendo.com/article/10.2478/scjme-2019-0009, in fig. 15-17.
9. I propose to rewrite the conclusions of the article. Now it is not clear what the authors propose that is new for world science and practice.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
1) In a large part of the text, an error appears when converting a document from .dock to .pdf format, such as:
The cooling rate was calculated and simplified by Eq. Error! Reference source not found. [35].
2) The paper does not show a comparative analysis or explanation with other materials and/or processing processes.
3) Ref. 16 is not fully defined (if the article is in a journal, there is no name of the journal or if it is a book, there is no publisher).
4) References may need to be innovated. Out of a total of 57 references, 5 of them are from 2020, there is not a single reference from 2021 and 4 are from 2022.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The manuscript is modified carefully. It is suggested to be accepted.
Reviewer 2 Report
Accept.
