Microstructure and Mechanical Properties in a Gd-Modified Extruded Mg-4Al-3.5Ca Alloy
, Dongqing Zhao 1,2,*, Shouqiu Tang 1, Yu Liu 3, Suqing Zhang 1,2, Yunteng Liu 1,2, Jianhua Wu 1,2, Xiaocun Song 1, Hongtao Liu 1,2, Xinfang Zhang 1, Pengfei Yan 1 and Xitao Wang 1,*Round 1
Reviewer 1 Report
This is essentially a run-of-the-mill, cook-and-look paper. However, the work is well carried out and the experimental investigation is thorough. Some simple thermodynamic calculations carried out by the present reviewer also indicate that the transformation of C36 into C15 can be expected. I only have two very minor comments:
-Don’t write “DRXed” in the abstract, write “dynamically recrystallized” (or “ dynamically recrystallized (DRXed)”)
-Expand the caption of Fig.3 with brief descriptions of Fig.3a)-f)
Author Response
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Reviewer 2 Report
The submitted manuscript discusses the Microstructure and Mechanical Properties in a Gd-modified Extruded Mg-4Al-3.5Ca Alloy. The alloys is of high importance for the transportation sector, and thus this study may be valuable for this industry. The manuscript is well structured and moderate English corrections are required. However, there are very important comments that must be answered by the authors to improve the quality of this submission. Detailed list of (general, major and minor) comments can be found in the attached file.
Comments for author File: Comments.pdf
Moderate English corrections are required.
Author Response
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Reviewer 3 Report
The purpose of the manuscript is to investigate the microstructure and mechanical properties of a Mg-4Al-3.5Ca-13 2Gd alloy after casting, heat treatment and extrusion conditions.
Please include in the manuscript the reason(s) for choosing Mg-4Al-3.5Ca-2Gd for the study, specifically the alloy contents of 4Al, 3.5Ca and 2Gd. Why not a different content?
Please include a phase diagram of the Mg-Al-Ca-Gd system so that the proposed homogenization treatment at 480oC can be justified and understood. Explain, based on the phase diagram, why the temperature of 480oC was chosen.
Figure 1D lists the possible compounds. It is highly recommended to perform complementary characterization, such as X-ray diffractometry (XRD). By performing XRD, speculative statements, such as the one in line 91: "It was believed that there are two main Ca-containing phases in Mg-Al-Ca alloys: Mg2Ca (C14) and Al2Ca (C15) [16]", would not be necessary.
XRD characterization is also required after heat treatment to confirm the phases listed in Fig. 2d.
Line 77: "Tests were performed three times for each condition." Since tests were performed in triplicate, the deviation needs to be included in the results.
Author Response
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