Effect of High-Pressure Torsion on Microstructure, Mechanical and Operational Properties of Zn-1%Mg-0.1%Ca Alloy
, Natalia Anisimova 1,2,3, Olga Rybalchenko 1, Mikhail Kiselevskiy 2,3, Georgy Rybalchenko 4, Natalia Tabachkova 3,5, Mark Zheleznyi 1,3,6, Dmitriy Prosvirnin 1, Dmitrii Filonenko 7, Viacheslav Bazhenov 3, Andrey Koltygin 3, Vladimir Belov 3 and Sergey Dobatkin 1,3Round 1
Reviewer 1 Report
This manuscript is dedicated to study of microstructure, phase composition, mechanical properties, corrosion resistance and bio- activity in vitro of Zn-1%Mg-0.1%Ca alloys after high pressure torsion (HPT). Obtained results in this work allow to conclude, that this alloy has a number of advantageous properties for its application in biomedicine. Abstract reflects the content of the paper, the methods of studies and some results/conclusions. In my opinion the results presented in this manuscript are interesting and original, however there are some shortcomings. I recommend publishing this manuscript after minor corrections given below:
1) There is no description of the machine for HPT, as well as information on the measurement of mechanical properties in tensile test (tensile machine name, sample sizes, measurement statistics). Please add these lack information in the Materials and Methods section.
2) In Fig.1a, describing the initial microstructure, cannot be seen the lamellar eutectic phase surrounding α-Zn dendritic cells. Please provide either a microphotograph at a higher magnification or a TEM microstructure, if possible.
The elemental SEM-EDS-mapping in Fig 1a must be in color. Please change it. The marker in Fig. 1c is poorly visible, as well as the letter e in Fig. 1е.
3) I believe that the presentation of tensile mechanical properties without tensile curves is incomplete. The reader may be interested in the shape and slope of the deformation curves. Please add them to the article, if possible. It will surely enrich your article.
4) Entering the corrosion degradation rate (DR) data into the Table 3, which mainly describes the mechanical property results, is confusing to the Reader. Since DR data do not change before and after HPT and, in addition, are already mentioned in the early text about corrosion properties, I propose to delete them from the Table 3.
Author Response
Dear Ms. Wang,
We would like to thank the reviewers for their valuable comments. We have considered them carefully and made some changes to the manuscript to address the criticisms. The alterations made are highlighted in colour. Our response to the critical points made by the reviewers is provided below.
Reviewer #1:
Q1: There is no description of the machine for HPT, as well as information on the measurement of mechanical properties in tensile test (tensile machine name, sample sizes, measurement statistics). Please add these lack information in the Materials and Methods section.
Response to Q1: We thank the reviewer for the valuable remark. Equipment data and details of mechanical testing have been added to Section 2.
Q2: In Fig.1a, describing the initial microstructure, cannot be seen the lamellar eutectic phase surrounding α-Zn dendritic cells. Please provide either a microphotograph at a higher magnification or a TEM microstructure, if possible.
The elemental SEM-EDS-mapping in Fig 1a must be in color. Please change it. The marker in Fig. 1c is poorly visible, as well as the letter e in Fig. 1е.
Response to Q2: The lamellae of the eutectic phase completely dissolve after homogenization and it becomes more homogeneous. We have added a SEM image of the eutectic phase where this is clearly visible. In addition, we have revised Figure 1 in accordance with the reviewer's comments.
Unfortunately, we have only black and white pictures due to equipment features. In the mapping images, each figure corresponds to an element that is identified in the composition of the corrosion product (it is marked in the lower right corner). The occurrence of white color in the image corresponds to the presence of the element being determined at a given place on the surface.
Q3: I believe that the presentation of tensile mechanical properties without tensile curves is incomplete. The reader may be interested in the shape and slope of the deformation curves. Please add them to the article, if possible. It will surely enrich your article.
Response to Q3: The tensile curves have been added to Section 3 (Fig. 6).
Q4: Entering the corrosion degradation rate (DR) data into the Table 3, which mainly describes the mechanical property results, is confusing to the Reader. Since DR data do not change before and after HPT and, in addition, are already mentioned in the early text about corrosion properties, I propose to delete them from the Table 3.
Response to Q4: The corrosion degradation rate (DR) values were deleted from Table 3.
Further minor changes (marked in the revised manuscript) have also been made. Also, the Section 2 (description of the methodology for studying bioactive properties) has been corrected in accordance with the request of the Editor. We now present the revised paper to the judgement of the reviewers and yourself as the Editor.
Sincerely,
on behalf of all authors
Dr. Natalia Martynenko,
Laboratory of Physical Metallurgy of Non-Ferrous Metals
A.A. Baikov Institute of Metallurgy and Materials Science
Russian Academy of Sciences, Moscow, Russia
Phone: +7 499 135 4425
Fax: +7 499 135 8680
Reviewer 2 Report
The topic is worth of investigation. The paper is well written and includes many interesting results. I have the following issues for discussion and correction:
1) Could you comment in more detail on the microstructure around points marked 2,3,4 and 5 in Figure 2? The grains in this are hardly recognizable. Is there an ultrafine grain structure or rather larger grains are dominant?
2) Indicate the measured physical parameter and its units (microhardness (MPa)) in Fig. 5b.
Author Response
Dear Editor,
We would like to thank the reviewers for their valuable comments. We have considered them carefully and made some changes to the manuscript to address the criticisms. The alterations made are highlighted in colour. Our response to the critical points made by the reviewers is provided below.
Reviewer #2:
Q1: Could you comment in more detail on the microstructure around points marked 2,3,4 and 5 in Figure 2? The grains in this are hardly recognizable. Is there an ultrafine grain structure or rather larger grains are dominant?
Response to Q1: Points 2-6 correspond to different areas of the eutectic phase, which was refined during HPT. It was noted above Fig. 2: «The phase located along the boundaries was also refined. The phase boundary zone consisted of fine grains of the refined phase with an average size of 38 ± 7 nm (Fig. 1d, Fig. 2a)».
Q2: Indicate the measured physical parameter and its units (microhardness (MPa)) in Fig. 5b.
Response to Q2: Fig. 5b was corrected.
Further minor changes (marked in the revised manuscript) have also been made. Also, the Section 2 (description of the methodology for studying bioactive properties) has been corrected in accordance with the request of the Editor. We now present the revised paper to the judgement of the reviewers and yourself as the Editor.
Sincerely,
on behalf of all authors
Dr. Natalia Martynenko,
Laboratory of Physical Metallurgy of Non-Ferrous Metals
A.A. Baikov Institute of Metallurgy and Materials Science
Russian Academy of Sciences, Moscow, Russia
Phone: +7 499 135 4425
Fax: +7 499 135 8680
