Effect of Al Content on Phase Compositions of FeNiCoCrMo0.5Alx High Entropy Alloy
Round 1
Reviewer 1 Report
The paper entitled "Effect of Al Content on Phase Compositions of FeNiCoCrMo0,5Alx High Entropy Alloy" is dealing with the analysis of structural and mechanical properties of the FeNiCoCrMo0.5Alx system.
On the whole the paper is well organized and written, the figures are clear and well described. Experimental methods are mostly well described, conclusions are clear.
There are some minor remarks addressed to the authors before the publication.
1. Sample preparation:
Relatively large samples (30g) were prepared and melted in an induction furnace in a quartz crucible. The process of preparing these samples requires a more detailed explanation, as the direct melting of metallic Molybdenum (T_m=2623C) with other elements having a much lower melting point (~1500C and even 660C for Al) in a quartz that melts at 1700C seems unreliable.
2. Fig. 9 presents NN distances for the detecteded cubic phases. It is also worth including the parameters of unit cells (also for sigma phase), e.g. in Table 2, where only the records of phases are presented.
3. It is worth comparing the obtained results and conclusions with the results of similar studies carried out on similar systems. For example, analogous studies of the phase composition as a function of Al concentration in a similar system, but without Mo, are presented in Journal of Alloys and Compounds 740 (2018) 264
4. The reference to Fig. 7 in the text has an incorrect number.
Author Response
We carefully read the comments of the reviewer and prepared answers
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The manuscript is well-written and its title of investigation is of interest to the readership. The existence of some points prevents its publication and must be addressed within the revised manuscript. The review comments are as follows:
-The introduction part needs extension by reviewing some relevant papers. The current number of refs is not sufficient. Doing this, reviewing the following refs might be helpful:
[a] IOP Conference Series: Materials Science and Engineering 1014 (1), 012018
[b] Journal of Alloys and Compounds 860, 158412
-Please add the microstructure of Al-free alloy for better comparison.
-In Fig.6, how do the authors calculate the vol fraction by XRD? What precautions did they follow for this analysis?
-Add Vol% in the y-axis of Fig.6.
-Fig.7 is not a meaningful and reliable demonstration of the paper concept.
-Fig.10, the detailed explanation on hardness reduction for Al=25 and 30 at% is required. It is better to be given by phase volume fraction.
Author Response
We carefully read the comments of the reviewer and prepared answers
Author Response File: Author Response.pdf
