Improving of Mechanical Properties of Titanium Alloy VT23 due to Impact-Oscillatory Loading and the Use of Carbon Nano-Solution
, Andrii Pylypenko 1, Jozef Brezina 5, Katarína Buzová 5 and Kostiantyn Lopat’ko 1Round 1
Reviewer 1 Report
Authors propose to improve the mechanical properties of titanium alloy plates through the use of carbon nano-solutions at a room temperature. In this case, the strengthening is achieved due to the formation of a special surface layer having an increased roughness and hardness. The authors using the XPS method showed that in the surface layer is formed a mixture of titanium oxide, titanium carbide or titanium oxycarbid.
However, it is not entirely clear from the text, how thick can a modified layer reach? Does the alloy's microstructure change after such treatment?
The text of the article requires some clarifications and corrections:
1. Line 164. I propose to replace “Mechanical results” by “Results of mechanical tests.
2. Lines 235-236 “specimens 55,56,57,58” - It is not clear how the samples were numbered. Were there any other sample numbers?
3. The term "static stretching". It is better to replace with a more suitable one: “tensile testing”.
4. Line 260. Cyrillic letters are present in the text.
5. Fig.2 - two images of the microstructure are shown at different magnifications. It is better to replace with one photo, and designate the structural components.
Author Response
Please see attached document for replies.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
In this manuscript, the authors examined improving of mechanical properties of titanium alloy VT23 due to impact- oscillatory loading and the use of carbon nano-solution. The authors are representing an interesting manuscript with novelty. The presented work in this manuscript is interesting, but nonetheless some changes, correction and clarifications should be introduced, in my opinion, untill publishable. I have the following comments:
1. In introduction it is indicated about effectiveness of method concerning the dynamic non-balance proces (DNP), but it is not presented information about different methods. Presenting advatages and disadvantages of these methods, can be strenghtened using of DNP.
The fragment including Lines 99-100, description of this study is too weak.
The structure of introduction is inconsistent, in my opinion.
2. In the paragraph first (Chapter 2), ‘room temperature’ is given, I suggest to indicate accurate temperature.
The more information concerning experimental research and prepared samples should be added.
3. Lines 117-119: indication of the literature [25] is not necessary.
4. For the parameters such as voltage amplitude, current, capacity of the energy storage device and frequency of the discharge pulse, were specified the ranges. I sugessted to indicate applied values of the parameters during the experiment in accordance with experimetal study; the lack of informaction concerning kind of exeperimetal study plan.
5. Please determine what are values of ‘optimal time’ and ‘long time’, ‘wide range’.
6. In the Figure 1, dimentional values should have units.
7. Line 139: You do not give information about types of carbon nanotubes and differences concerning concentration of the dispersed phase of carbon in aqueous solution.
8. Lines 142-144: The lack of information about amount of specimens with original surface and with polished surfaces.
9. In table 1, do the values of chemical composition have the relevant percentage contribution (wt. %)?
10. I suggest that the physical and mechanical properties of the alloy should be added.
11. The β-phase and α-phase should be determined in the Figure.
12. The fragment: The research was conducted in two stages. At the first stage, the optimal effect of the intensity of the impulse introduction of energy under impact-oscillatory loading on the maximum increase in the initial plastic deformation of the VT23 alloy was revealed for a batch of specimens. – should be indicated in the chapter 2 (Materials and Methods).
13. In Figure 4, the values of parameters and conditions, when using of DNP, should be indicated.
14. Line 213: the units of surface roughness parameters Ra and Rz in the initial state and after the DNP, should be indicated.
15. The values of Ra and Raz surface roughness parameters should be presented by using bar graph.
16. Lina 219: I suggest that the value of ‘the maximum improvement’ should be determined.
17. Line 248: ‘5d’ symbol should be instead of ‘5c’?
18. Line 260: ‘ні гірше по’ is it some phrase or mistake?
19. The conlusion describes the summary of results analysis and discussion. I suggest to focus on the significance of obtained information in the science field. Authors should be indicated futher directions of reserach.
20. Line 325: ‘3D Optical Surface Metrology System Leica DCM8’ – the information is unnecessary in conlusion.
Author Response
Please see attached file for replies.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
I believe that after making corrections, the manuscript can be accepted in present form.
Author Response
Dear reviewer,
using the MDPI english editing service we made recommended changes in the manuscript.
Thanks for Your time, professionalism, advice and recommendations!
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
