Influence of Die Surface Topography and Lubrication on the Product Quality during Indirect Extrusion of Copper-Clad Aluminum Rods

Round 1

Reviewer 1 Report

The work is quite informative, some suggestions which can improve it further are below :

The abstract is very informative

The introduction is well structured; however, it is very brief. Apart, there is not very clear which is the novelty of this study.

The citation style should be adapted to journal style  

Please provide details of heating rate and stabilization that allows to reach 330 °C

Can you please cite this “Usually a100 semi die angle around 30 ° is used for composite extrusion”

Also please cite this “To achieve the largest possible quasi-steady state during the extrusion, a
108 billet length of 105 mm was chosen. This is the maximum appliable billet length for the used extrusion 109 machine, operated in indirect extrusion setup. »

Please provide details of concetration proportion for « of a mixture of polyethylenes and graphite »

Extrusion Erials should be replaced with Extrusion Trials

There was used dye penetration for evaluation, which was reproduced by qualitative information, however it is worth to provide quantitative details of info too

Even the discussions are very lengthy they are not discussed against the literature. seems only authors opinion

In figure 15 were indicated some arrows but nothing about their meaning, please indicate what the authors observed there

The conclusion are good

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Dear Authors,

Major remarks:

1. The paper requires intensive editing. The are parts which are difficult to understand. In the paper there are used different symbols, variables or description which are not discussed (or presented) or they are explained much further in the text. Figures and references are not correctly prepared.

2. What was the influence of safety shutdowns for samples no.6-8? What about defects observed in Figure 8B? Is there correlation between these two effects?

3. Line 220-223:”To describe the heat development independently of the dies heating during the loading process, the difference between temperature at quasi-steady state TP, ss (s = 60mm) and initial temperature TP, ini at the beginning of the extrusion (s = 10mm) was chosen. ” - Variables should be corrected and Δtp should be defined.

4. Lines 257-259:”Due to the outstanding surface quality and sleeve integrity at trial No. 2, two additional cross sections (1B and 1C) were taken 100 mm and 150 mm behind the beginning of the intact copper sleeve to achieve a higher local resolution. ” It is difficult to understand. Such cross-section are not marked in diagram. Why these cross-section were not made for other samples? It can be seen on the example of the sanblasted sample that such two points may significantly change the shape of the curve.

5. Lines 281-286 and Table 2: It is difiicult to read, it should be given in line 281 that symbols (+) are marks used in the table2, i.e. (marked in table 2 as +). However, there is four symbols in table 2 but defined are only three in the text. It should be also given that some data are not available.

   Minor remarks:

6. Figure 1, line 117 : There are missing „Ø” before diameters.

7. Figure 3 should be improved – the illustration for oscillations of force can be given above the diagram

8. Figures 12-13 – please add number of samples in the figures. At the moment reader

9. Line 157 : „Extrusion Erials „ Please revise

Best Regards,

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

In this article author developed and implemented an alternation method for manufacturing copper-clad aluminum rods. The paper is well written and organized. It can be accepted with minor revision.

Introduction is in good shape. However, there are many new articles published in literature author need to focus on them and add to the introduction.

If possible, please add a cost analysis. If this processing is cheaper, how much cost this process can save compared to existing common process.

Please add the chemical composition of the material.

There are some typos. Please check the manuscript carefully.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Accept 

Reviewer 2 Report

Dear Authors,

Thank you for your response. I don't have any more remarks.

Best Regards.