Proof of Concept for Pultrusion Control by Cure Monitoring Using Resonant Ultrasound Spectroscopy

Round 1

Reviewer 1 Report

Although much further research needs to be done to prove the concept, the paper presents and explores an interesting idea. It would be interesting to apply the concept for higher pultrusion speeds.

 

Please see the following suggestions:

 

Line 5 - Replace "therefor" by "therefore"

 

Line 42 - Replace "culminates in in the glass transition" by "culminates in the glass transition"

 

 

Author Response

Thank you very much for your suggestions. I incorporated all of them into the paper.
Best regards,

Christian Pommer

Author Response File: Author Response.pdf

Reviewer 2 Report

J. Compos. Sci.

 

Manuscript ID jcs-866917

 

Title: Pultrusion Control by cure monitoring using Resonant Ultrasound Spectroscopy

 

This work aims to use the Pultrusion technique as an automotive manufacturing process for the fabrication of the composite materials. The results show that the Resonant Ultrasonic Spectroscopy has an effective role in in-line cure monitoring during the process. The aim of the present paper can be of technological interests but lack of scientific merits. The discussion and the ways that the evidences are presented do not really support their conclusions. Obviously, this article should not be accepted and published in the present state.

I am not going to details of papers, and the following comments are typical judging reasons.

1. Texts include some typing errors.
2. the references are limited and mostly for about ten years ago, so it should be updated for a research work.
3. The novelty of the work has not been specified in abstract/introduction. The originality of the research is not clear for readers. For a research article, the authors should highlight the originality of work in the abstract.
4. The introduction should include the research gap. Please rewrite the introduction to clear what is the actual problem of the process which your paper would like to resolve and the novel method (if involved) being used to solve the problem.
5. Please highlight that what's so special (or advantages) about your method compared to others in the same field of study (another researcher has not applied)?
6. How many samples being used in your study to confirm a consistent finding? Please clearly report the parameters for the welding process.
7. Figures 7-11: How about the samples containing defects? Will the finding be the same? What about mechanical properties in the presence of defects? Authors need to elaborate on this issue in discussion.
8. The work needs a clear discussion to support the finding, directing to the solution or suggestion. Support your discussion with references and theory.
9. Can you please provide some theoretical explanation of the Resonant Ultrasonic Spectroscopy and how it improves for in-line cure monitoring inside the pultrusion?

Author Response

Dear Reviewer,

thank you for your suggestions.

1) Typing errors hopefully all corrected

2) Even after extensive research no newer Papers where found. It is possible that there are papers at a different set of keywords which we did not find. If the reviewer has a particular paper in mind i would be gratefull for any suggestions.

3) We tried to highlight the research gap in the abstract and in the introduction

4) Please see point 2

5) I tried to add this to the introduction and abstract

6) The number of samples for this particular control scheme was only one but with an extended running time. The control scheme itself was tested on a simulation which was based on a multitude of previous experiments with the same sensor system in the same configuration as the later control scheme experiment as well as multiple DSC measurements for the epoxy system parameters.
An additional paragraph to highlight the number of samples used was added as well as one figure that highlights the difference sensor signal over pultrusion speed of previous experiments. Furthermore the title was changed to reflect that this paper should be seen as a proof of concept.

7) Smaller defects only add to the noise of the sensor system but have no overall influence. Bigger defects like the wedges shown in (now) Figure 15 can have a huge influence on the sensor signal especially when they create an air gap or a breakdown. I added a few paragraphs to highlight the influence on the sensor signal.

8) I rewrote the whole discussion

9) I added an extra paragraph to explain the basic working principle. For further explanation hower i think an extensive description would be overly long for this paper. The principles is explained in an earlier paper of mine referenced in this paper. If the explanation is still to short i will add a longer paragraph.

 

I added a diffed version for you where the changes between the new and old version are highlighted. The changes in the abstract could not be highlighted.

Best regards,

Christian Pommer

Author Response File: Author Response.pdf

Reviewer 3 Report

The authors have an interesting idea of cure-monitoring during the pultrusion process but the preliminary results presented in this paper are not very convincing. 

A machine learning approach may yield better optimization than the methods presented in this paper. 

This paper needs extensive changes as identified by the reviewer's comments.

Comments for author File: Comments.pdf

Author Response

Dear reviewer,

thank you for your comments. I directly incorporated all language corrections.

Furthermore:
Line 57: cur* is correct for I wanted to include curing as well cure
Line 61: it was not possible to get the papers in question but i am still on it. It is however highly possible that no full paper exist.
Line 80: corrected.
Line 122: Figures separated to sub figures.
Figure 10: A small paragraph was added. The small defect has no visible effect on the sensor signal and is the result of either internal release agent or a small wedge at the tool beginning.
General: Zoom in plots added
General: The slight angle of the ruler could only be corrected in post processing as the original material only partially still exists. I fear that a post processing might create imperfections exceeding the slight tilt. If the necessary I will address this.

I think as well that a machine learning approach is superior and currently in development. This paper however is only for demonstration that RUS can be used in pultrusion even with a more or less rudimentary control scheme.

I appended a diffed version of the paper to highlight the changes.

Best regards,
Christian Pommer

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The revised manuscript is much improved. The authors addressed my questions properly. The writing has been improved.

The experimental results of the paper can be of technological interests as well as scientific merits for the potential readers or researchers in field of research. The discussion and the ways that the evidence are presented support the results and conclusions.

Therefore, I recommend the revised manuscript to be accepted for publishing.

Reviewer 3 Report

The authors have made a great attempt at updating the manuscript with the suggested changes. The paper is still in its earliest stages of work and needs more additions to be published in this journal.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

This paper presents a report on the use of Resonant Ultrasound Spectroscopy for Cure Monitoring in pultrusion processing. The paper in this format is not suitable for publication in a journal. The paper is written more like an industry report with very vague statements. My suggestion is to provide more details on materials, design of experiments, results with some logical conclusions. The language also needs to be revised. Following mistakes should also be corrected. 

Need strong literature review in the introduction (what is the state of the art?)

Line 24 Can’t should be cannot

Line 25 What do you mean by general nature?

Line 34, 35 "Too little time"

Line 36 not following article, "this article"

Line 54 Held down

Figure 5: What is Pkrinciple pultrusion control?

Reviewer 2 Report

The paper deals with a very important subject and presents an interesting methodology. However, some of the results should be clarified. Moreover, it would be useful to include the dimensions of the pultrusion die and this is considered in the overall process