Initial Study of the Effect of Some PVD Coatings (“TiN/AlTiN” and “TiAlN/a-C:N”) on the Wear Resistance of Wood Drilling Tools

Round 1

Reviewer 1 Report

In this study, the authors have investigated the effect of different PVD coatings on the wear resistance of wood drilling tools. Authors have found that the TiN/AlTiN is better than the other coatings. State the novelty in abstract and introduction. Some improvements are recommended:

- There is a lack of literature survey. Authors should provide a literature survey on different coatings in the context of wood machining. Comparison of coatings as per issues in wood machining such as temp will be good.

- "During the experiments, the holes were drilled with the spindle speed of 4500 rpm and the feed rate of 0,35 m/min (feed per revolution - 0,15 mm)." the value of feed rate is not correct if you consider the feed per rev as 0.15 mm. It will be 0.675 m/min. Check if it is correct.

- "The final measurement (W) was given in millimeters." What is W, show this in one of the figures that will be easy to understand.

- Make Fig. 5, 6, and 7 identical. Start the plot in Fig. 5 and 7 with a number of holes 100.

- It would be better if the authors provide the images of the tool.

- Clearly state the reasons behind all the results.

- Check the conclusion part. Bullet and numbering both are shown.

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

General:

• The English grammar needs to be revised throughout the manuscript.
• Please use between 5 to 6 Keywords and make sure they are not included in the title and arranged alphabetically.

Abstract:

• It sounds weak when you use words like ‘initial’, ‘general data’. Please replace with different solid words.
• Do not use ‘i.e.’ in the abstract.
• In general, you want to: 1- provide a problem statement, 2- state your main research, 3- provide brief methodology, and the general outcome. Please revise.

Introduction:

• Authors need to elaborate more on the introduction section
• Please provide some insight on both CVD and PVD coating methods. This includes explaining the process, advantages and disadvantages. Also, make sure to focus more on the PVD technique because it is the main method used in the study. I suggest that the authors use the following sources in their manuscript, which provides good background on the PVD coating:

https://doi.org/10.3390/ma12040571

https://doi.org/10.1016/j.apsusc.2018.02.182

https://doi.org/10.3390/pr8080984

• The research gap is not clear. Ask yourself how is your work different from the available literature? You need to make this clear.
• You need to include a paragraph at the end of your introduction that states the steps that will be undertaken in the study (i.e., a brief methodology).
• In the same paragraph make sure to mention the advantage or how is your work going to enrich the scientific field.

Materials and Methods:

• For Figure 1, on the image, please include the names of the parts. You can use arrows to point on them and write their names.
• For Figure 2, please include images of the drill bit from the three groups (i.e., a sample from each group) for visual comparison.
• Did the authors perform the coating themselves or was the drill bit purchased coated? If they did the coating then on which bases was the parameters selected (i.e., film thickness, temperature, pressure, … etc.)?
• For Figure 3 and 4, please add some colours (i.e., coloured image).
• The authors mention that the ‘drill wear indicator (W) was determined using a microscope’. How was this done? You need to include more details.

Results:

• For all Plots, use colours and not black and white.
• Results outputs are fine but needs to be elaborated much more in terms of text. You need to explain to the reader what you have obtained and discuss their findings.
• For the ANOVA test results, it is not clear to me at all. Also, why didn’t the authors mention anything about it in the methods section? Please revise.

Conclusions:

• Elaborate more on this section. You cannot conclude with two bullet points.

           

 

 

Author Response

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Author Response File: Author Response.docx

Reviewer 3 Report

The paper "Initial study of the effect of some PVD coatings (" TiN / AlTiN "and" TiAlN / a-C: N ") on the wear resistance of wood drilling tools" presents experimental studies on the wear resistance of drills in wood drilling. The work is based on the comparison of the blade wear of 3 categories of drills. The paper could be published in "Forests" with some clarifications that could be brought by the authors:
- It could limit the number of bibliographic references, to its own works (there are 8 bibliographic references, 1-5, 8, 24, 26);
- Could make more accurate bibliographic references, instead of multiple ones (example "10-26" and "28-33");
- It could give indications on the coating installation with RF magnetron sputtering system;
- The technological deposition scheme could be improved (figures 3 and 4) by introducing an image with the tools covered in this study (4 drills were used each);
- It could provide information on how to measure the total thickness (approximately 4 μm in the work) and the thickness of each layer (approximately 5-10 nm and 30 nm).
- Could indicate the stature used to determine the basic physical and mechanical properties of the processed plate;
- It would be more convincing, however, to present, in tabular form, the experimental results on the basis of which the graphs in Figures 5-11 were drawn; an experimental schedule would have been very appropriate;
- Graphs could be redone using other ways to differentiate addictions (perhaps different collors), so as to facilitate understanding;
- It could offer explanations on figure 12, this is not found in the bibliographic reference [8];
- Could refer to figure 13 and explain the results of the ANOVA analysis;
- It could improve and justify the conclusions;

Thanks

Author Response

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Author Response File: Author Response.docx

Reviewer 4 Report

In this paper, the authors compared the service life of three kinds drill bits during drilling the wood particleboard. The method of statistical analysis was applied. Some experimental results were presented. It does not contribute to new knowledge in this field and does not represent enough scientific contribution whatsoever. Furthermore, it did not provide the detailed analysis of the coating microstructure and how they affected the wear resistance of the coated drill bits. This work only presents some experimental results and simple description, and lacks of in-depth theoretical analysis.

Some questions are as follows:

1. Authors did not mention the detailed images about the coating microstructure and phase constituents, they are very necessary to clarify the properties of the coated drill bits.
2. the English level must be improved, there are too many grammatical errors and poor expression to be understood.
3. References should be cited in order, for example the reference 27 was not cited.
4. a research paper should contain some necessary deep theoretical analysis. The experiment phenomenon could be explained by some evidence and measurement results. In this regard, the author needs to carefully revise and supplement.
5. Many symbols are lack of detailed comments and explanation. Such as what is the meaning of “P” and “R²” ? This makes it difficult for readers to understand.
6. Authors firstly demonstrated the Fig. 11 and Fig. 13, but the Fig. 12 was explained finally. The order is wrong.
7. the content in Fig. 13 is not clear, some symbols need to be clearly annotated.
8. The conclusion is inappropriate. It needs to be summarized again according to the experimental results.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

All suggestions and comments have been taken into account by the authors. 

Author Response

I have accepted all suggestions and modified the article. 

Author Response File: Author Response.docx

Reviewer 4 Report

The answers to questions 1 and 2 are far fetched. Additionally,  the detailed images about the coating microstructure and phase constituents must be provided before publication. Otherwise, the content of the paper is incomplete. 

Author Response

I have accepted all suggestions and modified the article. 

Author Response File: Author Response.docx