Investigation of the Thermal Conductivity of Silicon-Base Composites: The Effect of Filler Materials and Characteristic on Thermo-Mechanical Response of Silicon Composite

Round 1

Reviewer 1 Report

Comments to article applsci-1246570 entitled:

“Investigation on thermal conductivity of silicon-base composites: consequences of the filler’s features in the enhancement of k value”.

                                                                                                       

This article deals with the effect of different particles, metallic, ceramic, and carbonaceous used as fillers on the thermal conductivity of silicon-based composite materials. They study the effect of different structural parameters such us volume, dimension, morphology, etc., on this property. Curing of the silicon-based matrix is carried out by means of FT-IR analyzing the band located at 2160 cm-1 corresponding to Si-H bonds and also by DSC. The mechanical properties of the composites are also evaluated as wel as the thermal-mechanical properties by DMTA. Related to k

 

Although the article is interesting, some corrections and clarifications have to be carried out for improving the scientific content of the article in order to be published.

There are a few grammatical mistakes.

There are two Figure 7, in page 9 and in page 11. Please, modify them and the text in the article because can be confused.

The other one is in page 9 line 261. Authors said “Both spheroidal coper and dendritic….conductivity (Figure 7),..”. In my opinion, this figure is Figure 8, not 7. Please revise such errors.

Related to the scientific content of the article, there are some questions and suggestions.

For example, FT-IR spectra of Figure 1, the most important peaks are located below 2200 cm^-1. Then in order to visualize better, such spectra could start at that wavenumber, I mean, the range of  x-axis should be between 2200 and 500 cm^-1.    

Mainly, the fabrication of composites by using carbonaceous materials like carbon fibers, carbon nanotubes, etc., generates some defects in the composite because it is hard to mix such kind of fibrous materials. Do you visualize, by SEM microscopy, such defects or the composite is free of agglomerates? On the other hand, I was wondering if the low k value of carbon composites is due to the formation of agglomerates because if fibers are well dispersed, there is a percolation threshold in the structure and then thermal conductivity.

Authors mention, in chapter 3, Results and discussion, line 177 that “the goal of this study is …. dimension and surface/volume ration”. However, I do not find any data related to this parameter (surface/volume ratio) and it relation to thermal conductivity.. Please, if you mention this parameter, present some results and analyzing them.

 

Finally, in my opinion, conclusions must be short and only focused on the most relevant results of this research. However, reading such chapter, seems a summary of the article. Please, reduce the conclusion section only indicating the most important results.

Author Response

The answers are reported in the attached file

Author Response File: Author Response.docx

Reviewer 2 Report

1. The current study investigates the effect of adding fillers (metal particles, ceramic nano partic;es and carbon based materials) in silicon based composites on the resulting thermal conductivity and k value. For this the authors study different characteristics of filler materials such as their size, dimension, volume …etc.
2. The title of the manuscript can be improved, first of all it does not reflect what has been done in this paper. please consider making it read in a simpler way. For example remove the word consequences and just say: The effect of filler materials and characteristics on the thermo-mechanical behaviour (response) of silicon based composites. The authors make generic conclusion about their findings.
3. The authors said they studied thermo-mechanical properties in the abstract but that is also not reflected in the title
4. What is ATR, FT-IR analysis you need to mention what they stand for first time they appear in the manuscript
5. The abstract needs to be improved especially the findings, they are very generic and it is not clear what was actually concluded from this work!
6. Please consider reviewing the abstract and highlight the novelty, major findings and conclusions.
7. Line 30 the authors should avoid bulk citations unless they give full credit for the references somewhere else in the manuscript
8. After line 84 the authors should answer the following question: What is the research gap did you find from the previous researchers in your field? Mention it properly. It will improve the strength of the article
9. Add images and details of any equipment and tests carried out before or after the tests. This is an experimental study and the paper cannot be accepted unless the authors provide detailed description of the experimental work supported with figures.
10. Line 177-179 it is a bit confusing it seems the authors are not clear about what is the main purpose of this study, please keep it consistent in the abstract and elsewhere in the manuscript
11. Line 207 again I am confused when the authors say simulate do they mean a modelling process or something else? The word simulate was only mentioned once in the manuscript
12. Line 210 why please explain this further and support with references, also what about past studies what was their conclusion and findings on the effect of fillers on the curing kinetics?
13. Line 239 here the authors say they did tensile tests but before they said they only checked for thermal conductivity I think the authors need to be consistent everywhere in the manuscript
14. Combine figures 6 abnd 7 in one figure
15. Section 3.3 there is literally no discussion at all about the results, just reporting what we can clearly see from the graphs!
16. Line 135 and line 236, did the authors use cryogenic temperatures for this section?
17. The results are merely described and is limited to comparing the experimental observation. The authors are encouraged to include a discussion section and critically discuss the observations from this investigation with existing literature.

Author Response

The answers are reportedin the attached file

Author Response File: Author Response.docx

Reviewer 3 Report

Presentation of experiment results needs improvements because the paper makes impression of compacted measurements done by each Author separately. Figures put in Appendix (way selection unknown) impede the analyze of obtained results, and in my opinion that is not good. Some of them can be consolidated and all representative measurement as well as observation results should be presented traditionally, in article. The detailed comments are as follows:

 

• Chapter 3.2. Morphology of the composite (better Composite microstructure)

Microstructure of all composites should be presented, in case of nanofiller application for higher magnification only and the fillers should be indicated with arrows.

What is a difference in information in Figure 4 b and 4c?

• Captions of many  figures are incomplete,

 e.g. Figure S6. SEM of composite with dentritical  (dendritic?) Cu

There is no information about Cu content.

• Why the curves from tensile strength tests for materials with carbon, Cu and Ni fillers are not presented?
• What was the reason of so short mechanical stirring application for nanostructural fillers with liquid matrix mixing? Are the Authors sure that the uniform and agglomerate less mixture was obtained?

Author Response

the answers are reported in the attached file 

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Thank you very much for the corrections.

Reviewer 2 Report

All questions answered and paper can be accepted