Build Surface Roughness and Internal Oxide Concentration for Laser Powder Bed Fusion of IN718
Round 1
Reviewer 1 Report
This work studied the different oxide concentrations under different LPBF surface roughness. The different surface roughness was achieved by manipulating hatch spacings. The authors claimed to find a correlation between the surface roughness and oxide removal rate, however, the conclusions may not be scientifically sound due to the following reasons:
- This study lacks a discussion about the mechanism for oxide removal. Why does different surface roughness result in different levels of oxide removal? Is the main factor that causes oxide removal truly surface roughness, or hatch spacing (or potentially related to remelting volume, reheating temperature/time, etc.?)
- Surface roughness and oxide removal are both results of varying hatch spacings. There seems to be no causal relationship between surface roughness and oxide removal, as no mechanisms were proposed or discussed in the manuscript. Rather, the results of this work exhibit a clear causal relationship between the hatch spacing and the oxide removal, which is worth to be investigated.
Minor comments:
Figure 6: how was the broken line produced?
Figure 11: need SEM images to support the data
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The following are my observations:
- The motivation of work is not clear
- Novelty needs to be highlighted
- Literature review is missing
- What is the source for figure 1?
- How the equations for C and G are derived?
- How are the values for expected/ calculated plots in Figures 6, 9 and 10 obtained?
- Please justify the statement "The observed relationship 216
between build-surface roughness and incorporated oxide inclusions is consistent with a substantial role of removal of surface oxides during recoating" - How is the calculation performed to obtain Figure 12?
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The authors have successfully addressed my comments.
Reviewer 2 Report
The revised manuscript may be accepted for publication.
