Flow Behavior and Microstructure of Hot-Worked Fe-30.9Mn-4.9Al-4.5Cr-0.4C and Fe-21.3Mn-7.6Al-4.3Cr-1C Low-Density Stainless Steels
Round 1
Reviewer 1 Report
In this article, two low-density steels were adopted to gain the influence of hot working temperature and strain rate on flow stress and microstructural transformation. The following issues should be noted.
1. The authors must double-check the article's writing. For example:
a) In Line 108, Page. 3, “To determine if there is significant influence of deformation parameters on hardness of the alloys” should be “To determine if there is a significant influence of deformation parameters on the hardness of these alloys.”
b) In Line 123, Page. 4, “Figure 2” should be “Figure 4”.
2. Please supplement the nameplate of the workpiece shown in Fig. 1.
3. The title of Figure 5 is wrong.
4. In Line 162, Page 6, the authors consider “a rough flow oscillation depicting possible occurrence of discontinuous dynamic recrystallization.” It is an interesting phenomenon. The authors should describe it in detail.
5. In the Discussion, the authors indicate “… compared with heavily processed commercial grade 316 L stainless steel”. Please add the related references.
Author Response
- Response to reviewer’s comments
The authors appreciated the Editor for considering our manuscript for publication. We also appreciate the reviewers for the useful feedback. We have now revised the manuscript with the hope that the revised version has been improved to an acceptable standard. We provide a line by line to each of the comments raised.
In this article, two low-density steels were adopted to gain the influence of hot working temperature and strain rate on flow stress and microstructural transformation. The following issues should be noted.
- The authors must double-check the article's writing. For example:
- a) In Line 108, Page. 3, “To determine if there is significant influence of deformation parameters on hardness of the alloys” should be “To determine if there is a significant influence of deformation parameters on the hardness of these alloys.”
- b) In Line 123, Page. 4, “Figure 2” should be “Figure 4”.
Response: The authors agree that the manuscript needs a thorough language revision. Therefore, the manuscript was sent to a native speaker and a professional language editor for language editing. Comments 1 (a) and (b) have been duly addressed.
- Please supplement the nameplate of the workpiece shown in Fig. 1.
Response: Figure 1 has been changed to a supplementary figure. The remaining figures in the manuscript have been rearranged accordingly.
- The title of Figure 5 is wrong.
Response: The authors appreciate the reviewer for picking this up. We have now revised this accordingly.
- In Line 162, Page 6, the authors consider “a rough flow oscillation depicting possible occurrence of discontinuous dynamic recrystallization.” It is an interesting phenomenon. The authors should describe it in detail.
Response: The concept of flow oscillations as explained by Lutons and Sellars (1969) and Sakai and Jonas (1984) was described succinctly in the revised version of the manuscript. The dependence of flow oscillation on Zener-Hollomon parameter (temperature compensated strain rate) and most importantly ratio of initial grain size to that of dynamically recrystallized grains was included in the results section of the manuscript (Section 3.2).
- In the Discussion, the authors indicate “… compared with heavily processed commercial grade 316 L stainless steel”. Please add the related references.
Response: The statement has been revised and the relevant reference has been provided.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
1- This paper should be edited grammatically.
2- Highlight the main results in the abstract.
3- You should add quantitative results in the abstract.
4- The originality of the paper needs to be stated clearly. It is of importance to have sufficient results to justify the novelty of a high-quality journal paper. The Introduction should make a compelling case for why the study is useful along with a clear statement of its novelty or originality by providing relevant information and providing answers to basic questions such as: What is already known in the open literature? What is missing (i.e., research gaps)? What needs to be done, why and how? Clear statements of the novelty of the work should also appear briefly in the Abstract and Conclusions sections.
5- An updated and complete literature review should be conducted and should appear as part of the Introduction, while bearing in mind the work's relevance to this Journal and taking into account the scope and readership of the journal. The results and findings should be compared to and discussed in the context of earlier work in the literature.
Author Response
Response to reviewer’s comments
The authors appreciated the Editor for considering our manuscript for publication. We also appreciate the reviewers for the useful feedback. We have now revised the manuscript with the hope that the revised version has been improved to an acceptable standard. We provide a line by line to each of the comments raised.
1- This paper should be edited grammatically.
Response: The authors agree that the manuscript needs a thorough language revision. Therefore, the manuscript was sent to a native speaker and a professional language editor for language editing.
2- Highlight the main results in the abstract.
Response: The abstract has been revised and key results have been included.
3- You should add quantitative results in the abstract.
Response: The abstract has been revised and the peak stress result has been added. Although we have now exceeded the word limit for the abstract.
4- The originality of the paper needs to be stated clearly. It is of importance to have sufficient results to justify the novelty of a high-quality journal paper. The Introduction should make a compelling case for why the study is useful along with a clear statement of its novelty or originality by providing relevant information and providing answers to basic questions such as: What is already known in the open literature? What is missing (i.e., research gaps)? What needs to be done, why and how? Clear statements of the novelty of the work should also appear briefly in the Abstract and Conclusions sections.
Response: The authors appreciate the reviewer for this comment especially for the question prompts that were provided. The entire manuscript has been revised with emphasis on the abstract, introduction, discussion and conclusion. The authors would like to point out two things that we have done differently from the other authors.
- To the best of the authors’ knowledge, there is hardly any work that has considered hot working behaviour of as-cast Fe-Mn-Al-Cr-C low density steel with dendritic initial microstructure. We expect that the new microstructure we have obtained after deformation will improve the corrosion resistance of the alloys we have considered in our study. The results obtained will help in optimising process parameters for reproducible microstructure and mechanical properties.
- To the best of the authors’ knowledge we are the first group that is trying to repurpose Fe-Mn-Al-Cr-C low-density steels as alternative bio-implant materials. Other authors have focused mainly on automotive, structural and cryogenic applications, but the low elastic modulus exhibited by the alloys has been an impediment to adopting low-density steels as commercial alloys in these applications. With the search for less-expensive bio-implant alloy currently on-going, we have considered the low density, low elastic modulus and affordable cost of manufacturing these alloys as merits over existing bio-implant alloys such as 316L stainless steel and titanium alloys. The authors are exploring many other research aspects on the two alloys presented in this manuscript.
We hope this addresses the novelty question raised by the reviewer.
5- An updated and complete literature review should be conducted and should appear as part of the Introduction, while bearing in mind the work's relevance to this Journal and taking into account the scope and readership of the journal. The results and findings should be compared to and discussed in the context of earlier work in the literature.
Response: The literature has been updated. The entire manuscript has been revised with emphasis on the abstract, introduction, discussion and conclusion.
Author Response File: Author Response.pdf
Reviewer 3 Report
In this study, the authors produced two low-density steels of different grades, including duplex Fe-30.9Mn-4.9Al-4.5Cr-0.4C and austenitic Fe-21.3Mn-7.6Al-4.3Cr-1C using electric arc melting. They also determined their phase constituents using optical microscopy and x-ray diffraction analysis. The motivation of the work and the approach adopted are well. The manuscript is publishable after the below mentioned questions/comments are addressed.
Comments
1) What is the reason for the higher flow stress of Fe-21.3Mn-7.6Al-4.3Cr-1C microstructure with respect to Fe-30.9Mn-4.9Al-4.5Cr-0.4C? Please explain that.
2) The authors should compare their results with those reported for low density Fe–Mn–Al–C Steels. For example, see the following papers:
- Ivan Gutierrez-Urrutia, Low Density Fe–Mn–Al–C Steels: Phase Structures, Mechanisms and Properties, 2021 Volume 61 Issue 1 Pages 16-25
- Shangping Chen, Radhakanta Rana, Arunansu Haldar, Ranjit Kumar Ray, Current state of Fe-Mn-Al-C low density steels, Progress in Materials Science Volume 89, August 2017, Pages 345-391
3) The authors should compare the corrosion behavior of two synthesized microstructures in this study with that synthesis in the following paper.
- Juan Bosch , Ulises Martin, Willian Aperador , José M. Bastidas, Jacob Ress and David M. Bastidas, Corrosion Behavior of High-Mn Austenitic Fe–Mn–Al–Cr–C Steels in NaCl and NaOH Solutions, Materials 2021, 14, 425. https://doi.org/10.3390/ma14020425
4) page 12: This suggest that→ This suggests that
5) Page 12: The duplex low-density steel consist of→ the duplex low-density steel consists of
Author Response
The authors appreciated the Editor for considering our manuscript for publication. We also appreciate the reviewers for the useful feedback. We have now revised the manuscript with the hope that the revised version has been improved to an acceptable standard. We provide a line by line to each of the comments raised.
In this study, the authors produced two low-density steels of different grades, including duplex Fe-30.9Mn-4.9Al-4.5Cr-0.4C and austenitic Fe-21.3Mn-7.6Al-4.3Cr-1C using electric arc melting. They also determined their phase constituents using optical microscopy and x-ray diffraction analysis. The motivation of the work and the approach adopted are well. The manuscript is publishable after the below mentioned questions/comments are addressed.
Response: The authors appreciate the reviewer for considering our manuscript publishable.
Comments
1) What is the reason for the higher flow stress of Fe-21.3Mn-7.6Al-4.3Cr-1C microstructure with respect to Fe-30.9Mn-4.9Al-4.5Cr-0.4C? Please explain that.
Response: We have provided explanation on this. The higher carbon content in the austenite-based Fe-21.3Mn-7.6Al-4.3Cr-1C low-density steel was responsible for its higher flow stress.
2) The authors should compare their results with those reported for low density Fe–Mn–Al–C Steels. For example, see the following papers:
- Ivan Gutierrez-Urrutia, Low Density Fe–Mn–Al–C Steels: Phase Structures, Mechanisms and Properties, 2021 Volume 61 Issue 1 Pages 16-25
- Shangping Chen, Radhakanta Rana, Arunansu Haldar, Ranjit Kumar Ray, Current state of Fe-Mn-Al-C low density steels, Progress in Materials Science Volume 89, August 2017, Pages 345-391
Response: The authors appreciate the reviewer for recommending these papers. They were initially cited in the manuscript. We have now compared and discuss our results within the context of the results presented in the papers.
3) The authors should compare the corrosion behavior of two synthesized microstructures in this study with that synthesis in the following paper.
- Juan Bosch , Ulises Martin, Willian Aperador , José M. Bastidas, Jacob Ress and David M. Bastidas, Corrosion Behavior of High-Mn Austenitic Fe–Mn–Al–Cr–C Steels in NaCl and NaOH Solutions, Materials 2021, 14, 425. https://doi.org/10.3390/ma14020425
Response: The authors appreciate the reviewer for recommending this paper. Although not fully relevant to the current focus of this manuscript, it is very relevant to the broader context of our investigation on corrosion behaviour of deformed low-density steels.
4) page 12: This suggest that→ This suggests that
Response: This correction has been effected.
5) Page 12: The duplex low-density steel consist of→ the duplex low-density steel consists of
Response: This correction has been effected.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
No comments.
Reviewer 2 Report
accept in current form
