Features of Electron Beam Processing of Mn-Zn Ferrites in the Fore-Vacuum Pressure Range in Continuous and Pulse Modes
, Ilya Yu. Bakeev, Anna V. Dolgova, Andrey V. Kazakov, Nikita S. Korablev and Aleksey A. Zenin
Round 1
Reviewer 1 Report
The authors have written a manuscript entitled "Features of electron-beam processing of Mn-Zn ferrites in the forevacuum pressure range in continuous and pulse modes". This manuscript is interesting to be considered for acceptance. However, the following points should be considered:
Could you please present any XRD data confirming the structures of the samples?
Could you please the significance of the research in the abstract, introduction, and conclusion?
Author Response
Point 1: Could you please present any XRD data confirming the structures of the samples?
Response 1: We understand the importance of X-ray phase analysis and plan to include it in the description of our future research
Point 2: Could you please the significance of the research in the abstract, introduction, and conclusion?.
Response 2: We have made changes to the article:
Abstract: The results of electron-beam processing of Mn-Zn ferrite samples using pulsed and continuous electron beams in the forevacuum pressure range (10 Pa) are presented. We find that continuous electron-beam processing leads to surface structuring of the ferrite, changes in elemental composition on the surface, and electrical property modification. The degree of ferrite parameter changes exhibits a threshold behavior. For surface processing temperatures below 900 °C, changes are barely noticeable, while for temperatures over 1100 °C the surface resistance decreases by more than an order of magnitude to values of less than 3 kOhm. Electron-beam processing with millisecond pulse duration and pulse energy density exceeding 15 J/cm² results in the formation of low zinc content melt islands, while the remaining surface area (outside the islands) elemental content and ferrite properties remain largely unchanged. The thickness of the modified layer depends on the processing mode and can be controlled over the range 0.1–0.5 mm. Because of its low resistance, the modified layer can be utilized to enhance the RF-absorbing properties of the ferrite, which is important in the design of modern magnetic elements of electronic equipment.
page 2 line 47: The development of methods for modifying the structure of ferrite products has become an important task when designing modern magnetic elements of electronic equipment.
The importance is also presented in the conclusion page 15:
The reduction in resistance within the ferrite layer enables its utilization as an RF-absorbing material, expanding the applications of electron beam technologies.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This paper reported the microstructure and properties of the electron-beam processed Mn-Zn ferrites. The topic seems interesting; however, some issues are needed to be clarified.
1. Line 103, what does it mean “a homogeneous microstructure”?
2. Line 106, is the Mn0.6Zn0.4Fe3O3 a stoichiometric component?
3. Line 195, “A crystalline structure forms on the surface” that means the original Mn-Zn ferrites are amorphous?
4. Please explain why the pores formed at 900-1200 degree but not in 1300 degree.
5. Line 204, (f) 300 or 1300?
6. The effects of electron-beam on the metal surface were mainly due to the re-melting, therefore, the phase evolution and the resultant surface properties need to be focused on. Hence, please add the phase evolution with the electron-beam process parameter in the manuscript to identify the correlation between microstructure and properties.
7. In the manuscript, the resistivity rather than resistance is recommended to make a comparison.
8. Fig.8, three different values should correspond to three vertical coordinates.
The language is Ok
Author Response
Point 1: Line 103, what does it mean “a homogeneous microstructure”?.
Response 1: Unfortunately, a typo was made. The text of the article has been changed:
As evident from the image, the unprocessed surface of the 2000NM ferrite exhibits a structure composed of grains of non-uniform size.
Point 2: Line 106, is the Mn0.6Zn0.4Fe3O3 a stoichiometric component?
Response 2: Here it means that the composition obtained as a result of measurements is close to the composition typical for ferrite of this type
Point 3: Line 195, “A crystalline structure forms on the surface” that means the original Mn-Zn ferrites are amorphous?
Response 3: What is meant here is that the crystal structure becomes more visible in the surface layer. Changes have been made to the text of the article: Line 195, “The crystalline structure becomes more noticeable in the near-surface layer.”
Point 4: Please explain why the pores formed at 900-1200 degree but not in 1300 degree.
Response 4: Explanations are given on pages 7:
In SEM images of the surface taken at other magnifications, as shown in Figure 6, for 205 this sample, secondary recrystallization and the formation of a periodic microstructure 206 with a characteristic period of about 10 µm are visible. Simultaneously, the surface be- 207 comes smoother, and pores are filled with a melt that upon further crystallization forms a 208 flat surface.
Point 5: Line 204, (f) 300 or 1300?
Response 5: This is a typo. Of course the temperature is 1300 degrees Celsius. Changes have been made to the article.
Point 6: The effects of electron-beam on the metal surface were mainly due to the re-melting, therefore, the phase evolution and the resultant surface properties need to be focused on. Hence, please add the phase evolution with the electron-beam process parameter in the manuscript to identify the correlation between microstructure and properties.
Response 6: We understand the importance of X-ray phase analysis and plan to include it in the description of our future research
Point 7: In the manuscript, the resistivity rather than resistance is recommended to make a comparison.
Response 7: Yes, we agree, but there is a linear relationship between resistivity and resistance, so resistance was used in the article.
Point 8: Fig.8, three different values should correspond to three vertical coordinates.
Response 8: Only numeric values are represented on the vertical axis. The units of measurement of the studied quantities are shown in the figure
Author Response File: Author Response.pdf
Reviewer 3 Report
Title: On my opinion, the better word is fore-vacuum, or fore vacuum, rather than one word forevacuum. Suggest to change for all the words.
Abstract: Need to include also the important results, such as percentage of the elemental composition, electrical properties value, etc..
Overall, well-written manuscripts, well-analyzed data, good command of English, updated reference list.
Author Response
Point 1: On my opinion, the better word is fore-vacuum, or fore vacuum, rather than one word forevacuum. Suggest to change for all the words.
Response 1: We have replaced the word forevacuum with fore-vacuum
Point 2: Need to include also the important results, such as percentage of the elemental composition, electrical properties value, etc..
Response 2: We have added the ferrite resistance value after processing. The description of the elemental composition is presented in the text of the article and it will be difficult to correctly reflect the trends in its changes in the abstract.
Abstract: The results of electron-beam processing of Mn-Zn ferrite samples using pulsed and continuous electron beams in the forevacuum pressure range (10 Pa) are presented. We find that continuous electron-beam processing leads to surface structuring of the ferrite, changes in elemental composition on the surface, and electrical property modification. The degree of ferrite parameter changes exhibits a threshold behavior. For surface processing temperatures below 900 °C, changes are barely noticeable, while for temperatures over 1100 °C the surface resistance decreases by more than an order of magnitude to values of less than 3 kOhm. Electron-beam processing with millisecond pulse duration and pulse energy density exceeding 15 J/cm² results in the formation of low zinc content melt islands, while the remaining surface area (outside the islands) elemental content and ferrite properties remain largely unchanged. The thickness of the modified layer depends on the processing mode and can be controlled over the range 0.1–0.5 mm. Because of its low resistance, the modified layer can be utilized to enhance the RF-absorbing properties of the ferrite.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
The manuscript can be accepted in the present form.
