Effect of Glass Bubbles on Friction and Wear Characteristics of PDMS-Based Composites
Round 1
Reviewer 1 Report
This manuscript is presenting a study related to the improvement of the mechanical property of a PDMS material with the incorporation of glass bubbles. The manuscript is well-written and relatively easy to follow. I suggest major revision based on the following questions and comments?
- As the scope of the journal is regarding coatings and surface engineering solutions the authors should be more precise if the composite material is supposed to be used as a coating. In this context, they should provide also the thickness of the PDMS/GB coating, if it is a coating as it is not clear in the manuscript.
- The authors should use the S.I units, following the guide for authors, i.e. psi should be converted.
- I have several questions and suggestions related to the mechanical testing:
- Was a commercial device used to perform these experiments?
- What was the loading rate ?
- How were the forces measured during indentation and more importantly during the reciprocating tests.
- How was the indentation depth measured ?
- In lines 263-264 the statement regarding the typical COF of PDMS material must be supported by a reference.
- In line 306 the authors identified a process called “buffering”. Can they elaborate more on what is this buffering form the tribological point of view.
- The picture quality is quite low, for example the stress levels in Figure 4 are impossible to depict, rendering the Figure useless.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The article submitted for review describes the effect of the glass bubble additive to Polydimethylsiloxane on its mechanical properties (friction and wear characteristics). The authors summarize the current state of knowledge in a concise way. The included description of materials and methods allows for the complete reproduction of the study. In the experimental part, the authors presented a description of the very extensive research program they carried out. These included: surface measurements, elastic module measurements, finite element analysis, friction and wear characteristics. Special recognition is the fact that the authors made sure that their text was understandable for non-experts. Several times they translated the analysis carried out into simpler phrases, and the article is supplemented with graphics that illustratively explain the phenomena taking place.
The article is almost ready for publication. My only objection to the text is that the description of the used equipment should be compatible with MDPI formatting (model name, manufacturer, city where it was manufactured, country).
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
See the attached file.
Comments for author File: Comments.pdf
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
All my questions raised were adequately answered and therefore I agree to the publication of the manuscript.
