Review Reports

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Question 1

How does ultrasonic vibration superimpose on the face turning AMC components? Please explain the principle briefly and draw the working diagram of ultrasonic vibration superposition.

Question 2

What is the composition of the semi-metal brake lining material used for the pin in the friction test?

Question 3

Why do friction experiments need to be heated to 130 ^oC? What is the purpose?

Question 4

What is the wear mechanism of AMC surface morphology after friction test?

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This manuscript presents an experimental study on the preconditioning of the Aluminium matrix composites friction surfaces to avoid severe wear. The influence of AMC surface microedges by ultrasonic vibration superimposed face turning perpendicular to the direction of friction on speed and homogeneity of formed tribosurfaces is investigated. It is demonstrated that ultrasonic vibration superimposed face turning effectively generates microedges on the AMC surfaces, and that larger distances between the microedges enhance the formation of stable tribosurfaces that quickly lead to the tribosystem’s steady state. The findings contribute to the development of high performance AMC brake systems.

This manuscript presents reasonable structure and sufficient data. It can be considered for publication after some revision as follows:

1. Abstract needs to be refined and coherent.

2. The number of Reference references needs to be increased to be above 30, and Reference should cite more relevant journal articles published in the last 5-10 years.

3. The Conclusion provides a summary of the activities undertaken in this work. But the Conclusion needs to be refined and coherent.

4. There are some grammar, format and word errors in this paper. Please revise the document and make the necessary modifications.

Comments on the Quality of English Language

4. There are some grammar, format and word errors in this paper. Please revise the document and make the necessary modifications.

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The topic of this paper was suitable for submitting to this Special Issue of Advances in Machining of Difficult to Cut Materials. Many experimental analyses were performed in this study. The results and discussion are complete and reasonable. But I still have some questions.

Why did you use the AlSi7Mg as your experimental materials?

Why did you choose the reinforced with 35 vol.% SiC particles?

Please explain your reasons as above questions detailly.

The authors discuss the tribological surface conditioning by Pin-on-Disc Test, but I only see the surface roughness. There are no wear data in this paper.

On the other hands, there are no mechanical properties test in this paper, e.g. hardness test and tensile test. Because the mechanical tests can be used to predict the surface characteristics of the Aluminium matrix composites (AMC). I think that it is very important to explain more experimental results.

I found that the SEM explanation is so weak because the authors only focused on the wear surface, did not concentrate on the microstructures. Because the microstructure can affect the wear characteristics according to the materials science theory.

The vibration frequencies are also important parameters for microstructures and mechanical properties. In this paper, vibration frequencies were not considered. 

I also suggest that cited references should be added to over 25.      

Author Response

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Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

This paper investigated that the tribosurface formation between an AMC surface and a brake liner material  by microstructuring the AMC surfaces with using ultrasonic vibration superimposition face turning. The experimental results and discussions are expected to contribute to the development of the related technologies.

The AMC has hard silicon carbide particles as a reinforcing material for the aluminum base material. Therefore, please also describe in detail the effect of SiC particles on the ultrasonic vibration superimposition face turning.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

This revised manuscript was well written. Therefore, I recommend that this paper can be accepted for publication in JMMP without further revision.