Strategy for Surface Post-Processing of AISI 316L Additively Manufactured by Powder Bed Fusion Using Ultrasonic Nanocrystal Surface Modification
Round 1
Reviewer 1 Report
The submission has enough potential and could be considered for publication after being revised according to the following comments:
1) The SEM images in Fig 4 must be replaced with high mag images of various samples. Not much detail could be inferred from these micrographs.
2) The main deficiency of the current work is the lack of experimental data and evidence. The authors did different conditions (Table 3) but the given examined data is limited. too many schematic images are presented. I recommend the inclusion of experimental evidence.
3) It is recommended to characterize the UNSMed surfaces. It must be interesting to know whether the structure of AISI 316L would be changed by this treatment. The XRD could be an adequate candidate for this issue.
4) The evidence of the roughness test is suggested to be included in the revised context.
5) The experimental detail for hardness is required. In Fig. 10, should you change the hardness to microhardness?
6) 3D images in Fig. 11 could be questionable as the authors only selected one groove. How you can decide the trend comprehensively all over the surface? You need to show extended are to prove the trend.
7) The conclusion part is too long and needs abridgment.
8) In the references part too many papers are reviewed. Please exclude the outdated ones published before 2011-2012 and irrelevant ones. No need to cite this amount of refs for a research paper.
Author Response
We would like to express our deep gratitude for your sincere interest and kind remarks. We are also especially thankful for the kind suggestions of corrections. The submitted manuscript was revised considering the suggestions you have made.
Please, refer to the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
In this study, the rough surface of the 316 steel additively manufactured by powder bed fusion was post-treated by a new surface technique, namely ultrasonic nanocrystal surface modification. The experiments were designed and conducted in a very good standard and the conclusions are solid and convincing. It is therefore recommended for publication with only a few minor issues to be addressed, which are listed as follows,
- The structure of the whole manuscript could be organized in a better and clearer way. It is suggested that the authors should move the RSM and BBD analysis (i,e. Figure 5,6,7) to the end of the results or make it an individual section.
- There is currently no discussion section in the manuscript and the conclusion part is just too long. The authors are required to shorten the conclusion part and only highlight the key findings in this work. For example, "In future work, ....should be investigated", this should be in the discussion part.
- Figure 11. There is no label on the last figure (i.e. the 2D profile of the grooves) and the profile of the as-built (PBF) is also missing.
- There is no need to report the numerical values with too many digits, e.g. a hardness of 497.01 HV, 1.329 um. This should be rounded to 497 HV and 1.3 um.
Author Response
We would like to express our deep gratitude for your sincere interest and kind remarks. We are also especially thankful for the kind suggestions of corrections. The submitted manuscript was revised considering the suggestions you have made.
Please, refer to the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The revised manuscript could be considered for publication in Metals.
