Induction Skull Melting of Ti-6Al-4V: Process Control and Efficiency Optimization

Round 1

Reviewer 1 Report

The results presented in the article are of scientific interest and have practical significance. However, it should be noted that there are some minor comments on the article given below.
1. The novelty of the material should be stressed significantly in Title, Abstract, Text, and Conclusions.
2. The resolution of the figures (including the captions on the axes of the graphs) should be increased.
3. It is also necessary to expand the introduction by adding more information about the ISM method and properties of the material synthesized.

Author Response

Dear Reviewer,

many thanks for the time and interest that you have dedicated to our paper. In the same manner we appreciate your comments. Several paper improvements have been done according to the proposed suggestions:

1.     The novelty of the research has been stressed, giving more relevance to the Abstract, Text and Conclusions

2.     The resolution of the figures has been improved, focusing more attention in the captions of each graph.

3.     The introduction has been deeply rewriten, adding more relevant information related to ISM technology and titanium alloys. The information added has been also properly justified with several works published in the last 2016-2018 period.

* Changes in the text have been marked in red.

Author Response File: Author Response.docx

Reviewer 2 Report

Author’s affiliation:

As all authors come from the same Institute, please delete “1” after author’s name.

Accordingly, in the work of Dumont et al. (2009) they…

should be:

Accordingly, in the work of Dumont et al. they…

Please add the temperature measurement accuracy (for cooling water as well as for the melted zone).

In this context, the pyrometer correction (+31.5 °C) concerns the temperature range (700 °C to 1800 °C) or only the temperatures close to the melting point of titanium charge?

Is the power loss impacted by the sample mass?

The font size for the axes and legends of the figures should be increased for reading clarity.

Author Response

Dear Reviewer,

many thanks for the time and interest that you have dedicated to our paper. In the same manner we appreciate your comments. Several paper improvements have been done according to the proposed suggestions:

1.     “1” after authors affiliation has been deleted.

2.     The statement “Accordingly, in the work of Dumont et al. (2009) they…” has been corrected. (Line 119)

3.     Water and melt temperature measuring accuracy have been added

a.     0.1% in the water temperature (Line 152)

b.     0.1K at temperatures above 900ºC for the pyrometer value (Line 154)

4.     The pyrometer correction range has been defined for temperatures close to the titanium melting (Line 157)

5.     Yes, in both trials the initial Titanium ingot mass is 1kg, so the power loss impacted in the same manner. (Table 1)

6.     The resolution of the figures has been improved, focusing more attention in the captions of each graph

* Changes in the manuscript have been marked in red.

Author Response File: Author Response.docx

Reviewer 3 Report

The article "Induction Skull Melting of Ti-6Al-4V: process control 3 and thermal efficiency optimization" is written on the appropriate scientific level and can be interesting for the potential readers of the journal. The article is related to the research of effective optimization strategy of induction skull melting of Ti-6Al-4V, but the criteria of the effective optimization were not defined.  Meanwhile, the quality of the presentation must be improved. 

The abstract is adequate and includes the critical points of the research. 

The introduction is weak and must be completed by more relevant and current sources to present the actual state of the research topic internationally by the publications published in 2017-2019. It is recommended to finish the introduction by a declaration of the actuality and scientific significance of the work, consequent plan, and tasks of the research

Probably the Introduction is not the best place to show known formulas.

The materials and methods are described adequately for the researching area.

It is recommended to split the description of the results and discussion into two sections: Results and Discussion (of the results).

Figures 3,4,5,6,7 are not readable and must be improved.

Eq. 1-4 must be appropriately presented as it is recommended for scientific publications by grammar rules, and logic law (no "=", only consequent description of used symbols, where P is a force of..., etc.).

Conclusions could be suitable in the present form as it has countable and understandable data if in the discussion there are presented a step-by-step discussion of the obtained results according to the plan and tasks of the research, which must be mentioned at the end of the introduction.

It recommended mentioning the potential influence of the current research on the state of modern industry.

English must be checked.

17 positions for the list of references are not sufficient; it is recommended to mention at least 30-50 positions, 30% of them must be related to the manuscripts published in 2017-2019.

The paper is recommended for major revision.

Author Response

Dear Reviewer,

many thanks for the time and interest that you have dedicated to our paper. In the same manner we appreciate your comments. Several paper improvements have been done according to the proposed suggestions:

1.     The manuscript has been deeply rewritten and restructured improving the quality of the presentation and making clear the paper main objective and plan.

2.     The introduction has been rewritten, adding more relevant information related to ISM technology and titanium alloys. The information added has been also properly justified with several works published in the last 2016-2018 period. Finally, a declaration of scientific significance and research plan have been added.

3.     The calorimetric equations have been moved to a new subsection into Materials and methods

4.     The description of the results has been splitted in two sections: Results and Discussion

5.     The resolution of the figures has been improved, focusing more attention in the captions of each graph

6.     Equations have been adequately described according to scientific grammar rules.

7.     Conclusions have been improved, mentioning the potential influence of the current research.

8.     English has been checked in terms of grammar and spelling

9.     14 references haven been added to the previous 17 positions, 9 of them from the 2016-2018 period.

* Changes in the manuscript have been marked in red.

Round 2

Reviewer 3 Report

The authors rework significantly the manuscript. Introduction, Discussion, and Conclusions are updated according to the reviewers' comments. All sections are written on an academic level. The results of optimizations in cooling conditions for coil sub-assembly demonstrated increased process efficiency on 13% and shortened required melting time in more than 1 minute. The scientific significance of the work is in theoretical and experimental data for the development of more accurate induction heating numeric models, which can help in improvements of ISM technology and can be applied for the metalworking industry. 

The manuscript can be published in the present form.