The Effect of Cooling Rate on Microstructure and Mechanical Properties of the Zr-4Hf-3Nb (wt%) Alloy
Round 1
Reviewer 1 Report
The article is devoted to the research of alloys of zirconium with hafnium containing additives of niobium, iron, titanium, subjected to homogenization to a temperature of 600 and 850 degrees, followed by cooling at different rates. Interactive data on phase transformations are presented, and the influence of the formed phases on the strength properties of the material is revealed. The article may be useful for researchers dealing with these materials and can be recommended for publication.
Author Response
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Reviewer 2 Report
Dear Authors,
The study presents the tested material and its properties in a very reliable way. Then, the heat treatment was described and the research methodology was presented. A scientific thesis was presented and confirmed.
1) However, there is no conclusion in the summary stating what results were expected and what were obtained and whether the thesis put forward in the work was confirmed. The work is very extensive and its very thorough analysis allows the reader to draw such conclusions. However, the author does not show this.
2) Lines 68-75 describe the research carried out by the authors, which is detailed in part 2 - "Experimental". Lines 73-74 describe Vickers microhardness measurements. Lines 104-107 show the parameters of microhardness tests. In the section "3.3.2. Microhardness" the test results are discussed. However, the study lacks information on statistical data on the number of tested samples and the number of measurements made.
3) Types of cooling at different times FC-1; FC-2; FC-3 is described in lines 83-91, in my opinion the markings are ambiguous. Their parameters are not clearly presented in the article. What exactly does air walking (AC) and water walking (WC) mean
4) Figure 1 shows the heat treatment in a schematic way, which makes it very easy to read the article and illustrates what was done. However, the proportions on the time axis were not preserved. For example, heating takes twice as long as heating - which the graph does not show
As you can see, I have no substantive comments on the article. I think that after minor corrections, the article can be considered very good.
Kind regards,
Reviewer
Author Response
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Reviewer 3 Report
Dear Authors,
In this manuscript, the authors studied the phase, microstructure, and the mechanical properties of Zr-Hf alloy under different cooling rate. There are some problems related to editing/wording/expression. In my opinion, the manuscript entitled “The phase, microstructure, and their correlation with the mechanical properties of Zr-Hf alloy under different cooling rate” (authors: Shenglan Guo, Qi Wang, Xiangdong Xing, Yueli Du, Jianlu Zheng, Sunxuan Wang, Zhenghua Shen) is suitable for publication with minor corrections (Accept with minor revisions).
Few guidelines are given below.
1.I couldn’t understand well the label of the samples. Are these: FC-1, FC-2, F-3, AC, WC? If it is so, then the expressions as “sample with FC-3”, “the α phase of the sample with FC-1 presented the coarse grain size of 3.73 μm.”, “the α phase of the sample with WC” etc. are wrong.
2. The cooling rate of FC-1, FC-2, FC-3, AC, and WC were approximately 0.05, 0.10, 0.15, 5 and 1000 °C/s, respectively.
Probably should be replaced by
The cooling rate of FC-1, FC-2, FC-3, AC, and WC samples were approximately 0.05, 0.10, 0.15, 5 and 1000 °C/s, respectively.
3. When increased from FC-1 to FC-3, the samples had nearly the same and moderate values of YS
Probably should be replaced by
When the cooling rate increased from FC-1 to FC-3, the samples had nearly the same and moderate values of YS
Please, review the grammar/ expression throughout the manuscript.
Author Response
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Reviewer 4 Report
This submission vannot be accepted for publication for several reasons:
1. The chemical composition of the Zr-Hf alloy includes 4.47 wt.% Hf, see T.1. However, the EDS analysis shown in T.3. gives 5.11 and 11.96 wt.% in case of FC-1 and 5.00 and 8.26 wt.% in case of AC (phases alpha and beta). Since no other phases are present in the samples: Where does the surplus Hf come from? This is a hard contradiction.
2. The authors do not introduce the phases alpha, beta and omega. Most of the readears are probably not very familiar with the phase diagram of Zr-Hf, so they should be introduced.
3. The authors do not make clear how the phases were identified in OM and SEM, so the ascription seems quite arbitrary.
4. The fine omega particles in Fig. 8 cannot be seen.
5.The authors do not make clear how static toughness and yield ratio (Fig. 11) were determined.
6. There is absolutely no discussion of the results in the light of literature.
7. The submission is full of English mistakes, mainly concerning the tense and the singular/plural.
Author Response
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Author Response File: Author Response.pdf
