Hybrid Metal/Polymer Filaments for Fused Filament Fabrication (FFF) to Print Metal Parts

Round 1

Reviewer 1 Report

Dear Authors,
Thank you for your article investigating an important topic in additive manufacturing. Below you will find my comments.

1. Select an “article” in line 1.
2. In line 72 unnecessary move to a new paragraph in the middle of a sentence.
3. In lines 72 and 74, it is enough to state the name "AISI 316L".
4. It would be advantageous in Chapter 2 to illustrate schematically (e.g. by means of a drawing) the strategy for printing a sample from 17-4PH steel (described in lines 119-120 and shown at the fracture in Fig. 6).
5. In lines 134 and 138 (table 2 and 3) replace simbols with symbols.
6. Line 144: information about outsourcing should appear in a paragraph in rows 113-123, not 144.
7. Line 154, 176-177, 179: There is no reason to write the magnification, see more https://en.wikipedia.org/wiki/Magnification in “Magnification and micron bar”.
8. In line 210 replace 316l with 316L.
9. Table 5 should not show correct results for 316L and incorrect results for 17-4PH. The data in Table 6 should replace the data in Table 5.
10. Repeating the caption of Table 5 on lines 283-284.
11. Line 315: what does SSL316L mean? Is 316L not enough?

Author Response

#Reviewer 1

1. Select an “article” in line 1.

REPLY: Thanks we selected article

2. In line 72 unnecessary move to a new paragraph in the middle of a sentence.

REPLY: Thanks we modified the text accordingly.

3. In lines 72 and 74, it is enough to state the name "AISI 316L".

REPLY: Thanks we wrote AISI 316L only.

4. It would be advantageous in Chapter 2 to illustrate schematically (e.g. by means of a drawing) the strategy for printing a sample from 17-4PH steel (described in lines 119-120 and shown at the fracture in Fig. 6).

REPLY: The reviewer is right. To have a complete view we added in the supplementary materials the pictures of the internal structure as they were printed by markforged.

5. In lines 134 and 138 (table 2 and 3) replace simbols with symbols.

REPLY: Thanks we modified the text in the table accordingly.

6. Line 144: information about outsourcing should appear in a paragraph in rows 113-123, not 144.

REPLY: Thanks we erased the text in the line 144 and we left it in the line 113 as per reviewer’s suggestion

7. Line 154, 176-177, 179: There is no reason to write the magnification, see more https://en.wikipedia.org/wiki/Magnificationin “Magnification and micron bar”.

REPLY: on this point we disagree with the reviewer as in all the papers we published we reported two information for the SEM scan: mangnification degree and the scale bar. The two information are needed because the scale bar provides the visual measure of the artifacts shown while the magnification gives the reader the feedback about one important parameter used in the analysis.

8. In line 210 replace 316l with 316L.

REPLY: Thanks we corrected the text accordingly.

9. Table 5 should not show correct results for 316L and incorrect results for 17-4PH. The data in Table 6 should replace the data in Table 5.

REPLY: on this point we disagree with the reviewer as we believe a focal point of our paper is to show that some data reported in the literature underestimated the load bearing area and therefore the mesostructure should be taken into account. This is something like the use of engineering stress and strain in place of true stress and strain as it is commonly done in the practice.

10. Repeating the caption of Table 5 on lines 283-284.

REPLY: as the point 9 we disagree on this.

11. Line 315: what does SSL316L mean? Is 316L not enough?

REPLY: thanks we modified the text accordingly.

 

Author Response File: Author Response.docx

Reviewer 2 Report

There are some weaknesses through the manuscript which need improvement. Therefore, the submitted manuscript cannot be accepted for publication in this form, but it has a chance of acceptance after a major revision. My comments and suggestions are as follows:

1- Abstract gives information on the main feature of the performed study, but some more details about the experiments should be added. However, a concise abstract is needed.

2- The necessity of the presented study must be explained in introduction. Differences with previous studies?

3- Introduction is short and the literature study must be enriched. Based on the discussed topics in the manuscript (3D printing, mechanical tests), it is highly recommended to read and cite following papers published in high ranking journals: https://doi.org/10.1002/nme.4936 and https://doi.org/10.1016/j.eml.2020.100692 and https://doi.org/10.1021/acsapm.0c00103

4- Authors must clarify why this particular type of material was examined.  Specimen’s figures (illustrated in tables) must be presented in a higher quality.

5- As this is an experimental research, it is necessary to present some figures of experimental work. For instance, specimen under tensile test (3.2.2).

6- Authors discussed cost, and it would be nice if they can refer to https://doi.org/10.1016/j.apmt.2020.100689 for environmental impact of the utilized 3D printing process.

7- The conclusion is too short and it must be more than just a summary of the manuscript. Please provide all changes throughout the manuscript and reference updates by red color in the revised version.

 

 

Author Response

#Reviewer 2

1- Abstract gives information on the main feature of the performed study, but some more details about the experiments should be added. However, a concise abstract is needed.

REPLY: We understand the point raised by the reviewer but the abstract, according to the Journal guidelines, should be limited to 200 words only and it is currently very close to the limit (198 words). Therefore, due to the fact that tensile testing is carried out under international ASTM standards we preferred not to include a description as these methods are well known.  

2- The necessity of the presented study must be explained in introduction. Differences with previous studies?

REPLY: We added the following text “Therefore, we intended to expand the study by using a low cost printer for the Ultrafuse 316L that has not been reported before as the standard parameters given by BASF have been obtained on Ultimaker series machines. In addition to that, a detailed analysis of the mesostructure and of the influence of real load bearing area was reported in this paper.”

3- Introduction is short and the literature study must be enriched. Based on the discussed topics in the manuscript (3D printing, mechanical tests), it is highly recommended to read and cite following papers published in high ranking journals: https://doi.org/10.1002/nme.4936 and https://doi.org/10.1016/j.eml.2020.100692 and https://doi.org/10.1021/acsapm.0c00103

            REPLY:  we thank the reviewer for the valuable suggestions. We report in the following table the extended references and shortly report what has been added to the paper and what has not been added with an explanation for the choice.  

 

Reference suggested	Added	Note
Application of RKP‐FSM in the buckling and free vibration analysis of thin plates with abrupt thickness changes and internal supports Mani Khezri  Mark A. Bradford  Zora Vrcelj First published: 11 April 2015 https://doi.org/10.1002/nme.4936Citations: 5	NO	The paper suggested is about vibration and it does not refer to AM parts.
Extreme Mechanics Letters Volume 37, May 2020, 100692 Extreme Mechanics Letters Fracture and load-carrying capacity of 3D-printed cracked components Mohammad Reza Khosravania and  Ali Zolfagharianb	YES
Synthesis of PEG and Quaternary Ammonium Grafted Silicone Copolymers as Nanoemulsifiers Srishti Gupta, Pummy Singh, Babak Moghadas, Bradley J. Grim, Vikram D. Kodibagkar, and Matthew D. Green* Cite this: ACS Appl. Polym. Mater. 2020, 2, 5, 1856–1864	No	The paper refers to Nanoemulsifiers that have no correlation with the submitted paper
Applied Materials Today Volume 20, September 2020, 100689. On the environmental impacts of 3D printing technology Mohammad Reza Khosravani Tamara Reinicke	YES

4- Authors must clarify why this particular type of material was examined.  Specimen’s figures (illustrated in tables) must be presented in a higher quality.

REPLY: Thanks for the suggestion we improved the figures quality.

5- As this is an experimental research, it is necessary to present some figures of experimental work. For instance, specimen under tensile test (3.2.2).

REPLY: Thanks for the suggestion we added in the supplementary materials a picture (Figure S2) showing the tensile testing.  

6- Authors discussed cost, and it would be nice if they can refer to https://doi.org/10.1016/j.apmt.2020.100689 for environmental impact of the utilized 3D printing process.

            REPLY: Thanks for the suggestion we added a comment in the discussion and the interesting reference outlined by the reviewer.

7- The conclusion is too short and it must be more than just a summary of the manuscript. Please provide all changes throughout the manuscript and reference updates by red color in the revised version.

REPLY: We thank the reviewer for the suggestion. We added the following text in the conclusion

“This cost modelling did not account for the environmental impacts of the processes. However, as  recently shown by some authors [28], the choice of the AM process can impact on the environment differently. For example, Giudice et al [29] showed that SLM processing has an high energy consumption. This can be overcome by the use of the hybrid metal-polymer filaments presented in this study that envisages the use of simple desktop FFF machines that are operated at much lower electric power.”

 

 

 

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

In the submitted revised manuscript, most of the reviewers' comments have been properly responded. I think, it can be considered for publication in Applied Sciences.

Author Response

The reviewer #2 reported the following comment

 

In the submitted revised manuscript, most of the reviewers' comments have been properly responded. I think, it can be considered for publication in Applied Sciences.

 

Therefore as nothing was suggested as further improvement it is not clear what should be modified more