Study on Cavitation Corrosion Properties of Titanium Alloy Radiation Rod with Different Roughnesses for Ultrasonic Casting
Round 1
Reviewer 1 Report
The greater the roughness of the solid interface, the greater the maximum pressure in the process of cavitation bubble collapse. Some comments given as follows:
1. Line 26, In the present form, actually nothing really novel. The current works appears to be a replication or modified literature according to the lack of novelty. The authors must extensively describe the novel in their work. This work should be rejected due to a serious concern.
2. Line 35, it is nothing other than UST? Please provide others possible solution.
3. Line 60, before the authors specifically mentioned titanium alloy as investigated materials, please explain before the rationalisation of titanium alloy characteristic and comparison with others materials, such as stainless steel and cobalt chromium molybdenum. For this issue, please provide the explanation along with relevant information as follows: https://doi.org/10.3390/ma14247554
4. Line 71, please revise it with “…..[23], surface morphology [24], and others.”.
5. Line 85, where is the data of Contents of major solute elements in the TC4 (wt.%) adopted? It is from previous literature? Please giving the reference.
6. Line 86, please give the illustration of sample illustration, in the figure 1 not specific shows the specimens.
7. Line 128, comprehensive discussion to highlight Weightlessness of each group of samples. Is mandatory.
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Author Response
Point 1: Line 26, In the present form, actually nothing really novel. The current works appears to be a replication or modified literature according to the lack of novelty. The authors must extensively describe the novel in their work. This work should be rejected due to a serious concern.
Response 1: Thanks for your comment. The cavitation corrosion mechanism of titanium alloy radiation rods with different roughness in 2A14 ultrasonic cast aluminum melt was studied. In this work, the damage mechanism of radiation rod was explored and analyzed. This was beneficial for the later improvement of the radiation rod to avoid excessive damage. There is very little literature on cavitation corrosion of ultrasonic rods used in melt casting, so we have not been able to find relevant literature. A lot of work had been done to study the corrosion mechanism of the radiation rod by ultrasonic cavitation by combining simulation and experiment. Perhaps the innovation of this article was not very significant, but the guidance for actual production was very meaningful. In future research, the authors will conduct more in-depth research on the comments provided by the reviewers. Thank you again for your suggestion.
Point 2: Line 35, it is nothing other than UST? Please provide others possible solution.
Response 2: Thanks for your comment. We have added references to 3D printing, powder metallurgy, die-casting, electromagnetic stirring, and semi-solid forming technologies. As referenced in reference [11-15] (in red).
Point 3: Line 60, before the authors specifically mentioned titanium alloy as investigated materials, please explain before the rationalisation of titanium alloy characteristic and comparison with others materials, such as stainless steel and cobalt chromium molybdenum. For this issue, please provide the explanation along with relevant information as follows: https://doi.org/10.3390/ma14247554
Response 3: Thanks for your suggestion. Reference [25] has been added to the paper (in red).
Point 4: Line 71, please revise it with “…..[23], surface morphology [24], and others.”.
Response 4: Sorry for this incorrect statement. We have revised it. “This include pressure gradient on the surface of the radiation rod, material properties [28, 29], and surface morphology [30, 31], and others”. (in red).
Point 5: Line 85, where is the data of Contents of major solute elements in the TC4 (wt.%) adopted? It is from previous literature? Please giving the reference.
Response 5: Thanks for your comment. Reference [36] has been added to the paper (in red).
Point 6: Line 86, please give the illustration of sample illustration, in the figure 1 not specific shows the specimens.
Response 6: Thanks for your suggestion. Sample example has been added in Figure 1 (in red).
Point 7: Line 128, comprehensive discussion to highlight Weightlessness of each group of samples. Is mandatory.
Response 7: Thanks for your comment. We have emphasized and discussed weightlessness of each group of samples. After 48 minutes of experiment, samples A: 0.4 Ra, B: 7.2 Ra, C: 9.5 Ra and D: 9.8 Ra lost 8.1mg, 12.7mg, 17.3mg, and 15.4mg in weight, respectively. Samples A lost the least weight, while sample C lost the most weight. The rougher the surface, the more pits there are. The greater pits results in a greater contact area between the pit and the aluminum melt. The aluminum melt rapidly spreads on the surface of the titanium alloy, leading to a higher rate of diffusion, chemical reaction, and recombination of Ti atoms in the aluminum melts. (in red).
Author Response File: 
Author Response.docx
Reviewer 2 Report
Kindly find my minor revision comments for this article to improve its quality before acceptance in this reputed journal:
1. Specify the range of roughness values for each sample (e.g., A: 0.4 Ra, B: 7.2 Ra, etc.)
2. Clarify the purpose and significance of studying the cavitation corrosion behavior of radiation rods in the context of ultrasonic casting.
3. Provide more context on the significance of the "incubation period of cavitation corrosion" and why it's relevant.
4. Please ensure that the figure captions are concise and provide sufficient information to understand the content of the figures. Consider adding more detailed descriptions of the images in Figures 5, 6, and 7 to help readers comprehend the observations.
5. In several sentences, the phrasing can be improved for clarity. For example, in the first sentence of the abstract, consider rephrasing: "The ultrasonic vibration resulted in the formation of small reactants on all surfaces." This could be clearer as: "Ultrasonic vibration led to the formation of small reactants on all surfaces."
6. Avoid using overly complex sentence structures. Break down long sentences into smaller ones to enhance readability.
7. Ensure consistent formatting of equations and symbols throughout the text.
8. When introducing new symbols or variables, provide explanations or definitions for them.
9. In Section 3.4, provide a brief explanation of the significance of the microhardness results. How do the observed changes in microhardness relate to the overall findings of the study?
10. In Section 3.5, when discussing the simulation setup and assumptions, clarify why certain assumptions were made and their impact on the accuracy of the simulation results.
11. Ensure consistent use of terminology and symbols throughout the article. Avoid using different terms to describe the same phenomenon.
12. In several places, the same information seems to be repeated using slightly different wording. Review the text to eliminate unnecessary repetition and ensure a concise presentation of the results and discussions.
13. In the introduction, provide more context for the study. Why is the interaction between Al/Ti interface and ultrasonic vibration important? What applications or industries might benefit from this research?
14. In the abstract, consider summarizing the key findings and their implications for practical applications.
15. In the conclusion, reiterate the main outcomes and their significance for the field of study. Highlight any recommendations or directions for future research.
16. Clearly define the terms used in equations (1) and (2) before presenting the equations.
17. Mention the units (mg/min) of the weight loss rate in Table 3 for clarity.
18. Clarify how the roughness values affect the rate of weight loss for better readability
19. Provide more context on the practical implications of the weight loss rates observed.
20. Explain the observed plastic deformation in terms of the cavitation process and its implications for material damage.
21. Provide more explanation on how the continuous etch pit formation process contributes to material damage.
22. Describe the differences in evolution processes of surface morphology between different roughness levels.
23. Clarify the significance of identifying TiAl3 as the corrosion product.
24. Elaborate briefly on the role of TiAl3 in the corrosion process.
25. Proofread the manuscript for minor grammatical errors and sentence structure issues.
26. Ensure consistent use of units, especially when presenting experimental data.
27. Add recent literature such as: 10.1088/1742-6596/2267/1/012079, https://doi.org/10.3390/app13020730
Minor editing of the English language required
Author Response
Point 1: Specify the range of roughness values for each sample (e.g., A: 0.4 Ra, B: 7.2 Ra, etc.)
Response 1: Thanks for your suggestion. We have specified each sample in the entire text as follows: A: 0.4 Ra, B: 7.2 Ra, C: 9.5 Ra and D: 9.8 Ra (in red).
Point 2: Clarify the purpose and significance of studying the cavitation corrosion behavior of radiation rods in the context of ultrasonic casting.
Response 2: Thanks for your suggestion. The purpose and significance of studying the cavitation corrosion behavior of radiation rods in the context of ultrasonic casting is clarified. In the process of ultrasonic casting, the life of radiation rod is seriously attenuated due to cavitation corrosion. It is an important reason limiting the popularity of ultrasonic casting industry. ( in red).
Point 3: Provide more context on the significance of the "incubation period of cavitation corrosion" and why it's relevant.
Response 3: Thanks for your suggestion. We have provided more context on the significance of the "incubation period of cavitation corrosion" and reference [37]. The entire process of cavitation corrosion includes the incubation period of cavitation and acceleration period of cavitation. The duration of the cavitation incubation period increases linearly with the increase of the roughness of the material surface morphology. And the original traces generated by machining on the material surface have a significant impact on it [37] (in red).
Point 4: Please ensure that the figure captions are concise and provide sufficient information to understand the content of the figures. Consider adding more detailed descriptions of the images in Figures 5, 6, and 7 to help readers comprehend the observations.
Response 4: Thanks for your suggestion. We have revised the figure captions (in red) and added more detailed descriptions of the images in Figures 5, 6, and 7 (in red).
Point 5: In several sentences, the phrasing can be improved for clarity. For example, in the first sentence of the abstract, consider rephrasing: "The ultrasonic vibration resulted in the formation of small reactants on all surfaces." This could be clearer as: "Ultrasonic vibration led to the formation of small reactants on all surfaces.".
Response 5: I’m so sorry for the “the ultrasonic vibration resulted in the formation of small reactants on all surfaces”. I can’t find this sentence in the first sentence of the abstract. Perhaps I didn't understand the reviewer's meaning.
Point 6: Avoid using overly complex sentence structures. Break down long sentences into smaller ones to enhance readability.
Response 6: Thanks for your suggestion. We have broken down long twelve sentences into smaller ones (in red).
Point 7: Ensure consistent formatting of equations and symbols throughout the text.
Response 7: Sorry for the wrong consistent formatting of equations and symbols. We have revised them in the text (in red).
Point 8: When introducing new symbols or variables, provide explanations or definitions for them.
Response 8: Thanks for your suggestion. We have provided explanations for the new symbols or variables. “The radius of cavitation bubbles R”, “Where n and l are defined as the number of phases and sampling length, respectively.” (in red).
Point 9: In Section 3.4, provide a brief explanation of the significance of the microhardness results. How do the observed changes in microhardness relate to the overall findings of the study?
Response 9: Thanks for your suggestion. We have provided a brief explanation of the significance of the microhardness results and the changes in microhardness relate to the overall findings of the study. At this time, the cavitation energy absorbed by the plastic deformation of the material had reached saturation. Then the microhardness gradually decreased, which caused the surface material to detach from the matrix and underwent processing softening. At the same time, as the newly exposed surface was subjected to cavitation impact, the larger hardened layer of the material moved towards the interior of the matrix. The rate of surface material detachment was lower than the rate of high hardened layer hardening towards the interior. (in red).
Point 10: In Section 3.5, when discussing the simulation setup and assumptions, clarify why certain assumptions were made and their impact on the accuracy of the simulation results.
Response 10: Thanks for your suggestion. We have clarified why certain assumptions were made and their impact on the accuracy of the simulation results in section 3.5. The inertial force and surface tension have little influence on the whole calculation result, and the calculation amount is large, so they are ignored. In order to ensure the accuracy of simulation results, the amount of gas in the cavity must be kept constant. (in red).
Point 11: Ensure consistent use of terminology and symbols throughout the article. Avoid using different terms to describe the same phenomenon.
Response 11: Thanks for your comment. We have revised them, for example the “cavitation corrosion”(in red).
Point 12: In several places, the same information seems to be repeated using slightly different wording. Review the text to eliminate unnecessary repetition and ensure a concise presentation of the results and discussions.
Response 12: Thanks for your comment. We have revised the same information using slightly different wording and streamlined some of the results and discussions (in red).
Point 13: In the introduction, provide more context for the study. Why is the interaction between Al/Ti interface and ultrasonic vibration important? What applications or industries might benefit from this research?
Response 13: Thanks for your comment. This paper’s title is “Study on cavitation corrosion properties of titanium alloy radiation rod with different roughness for ultrasonic casting”. The introduction introduces a lot of background about ultrasonic casting. We explore the influence of ultrasound on Al/Ti interfaces with different roughness levels. This is the main content of our research, so that it is no longer to provide more context. The casting industry might benefit from this research.
Point 14: In the abstract, consider summarizing the key findings and their implications for practical applications.
Response 14: Thanks for your comment. We have added “This study provide an insight to develop a new homemade Ti alloy radiation rod with better resistance to corrosion in the ultrasonic casting” to the abstract. At the same time, we simplify the abstract to within 200 words. (in red).
Point 15: In the conclusion, reiterate the main outcomes and their significance for the field of study. Highlight any recommendations or directions for future research.
Response 15: Thanks for your suggestion. In the conclusion, we have reiterated the main outcomes and their significance for the field of study and highlighted recommendations or directions for future research. Additionally, research has thus far concentrated on the properties of titanium alloy radiation rod with different roughness in 2A14 aluminum melt for ultrasonic casting. The influence of different roughness is only one factor in the ultrasonic casting process. We can also study the effect of different power ultrasound on the corrosion performance of radiation rods. This will help us understand the corrosion mechanism of titanium alloy radiation rods throughout the entire ultrasonic casting process and also provide an deeper insight to develop a new homemade Ti alloy radiation rod with better resistance to corrosion in the ultrasonic casting. (in red).
Point 16: Clearly define the terms used in equations (1) and (2) before presenting the equations.
Response 16: Thanks for your comment. The terms used in equations (1) and (2) are defined. (in red).
Point 17: Mention the units (mg/min) of the weight loss rate in Table 3 for clarity.
Response 17: Thanks for your suggestion. We have added the units (mg/min) of the weight loss rate in Table 3 (in red).
Point 18: Clarify how the roughness values affect the rate of weight loss for better readability.
Response 18: Thanks for your comment. The rougher the surface, the more pits there are. The greater pits results in a greater contact area between the pit and the aluminum melt. The aluminum melt rapidly spreads on the surface of the titanium alloy, leading to a higher rate of diffusion, chemical reaction, and recombination of Ti atoms in the aluminum melts (in red).
Point 19: Provide more context on the practical implications of the weight loss rates observed.
Response 19: Thanks for your suggestion. We have added more context on the practical implications of the weight loss and reference [31] in introduction (in red).
Point 20: Explain the observed plastic deformation in terms of the cavitation process and its implications for material damage.
Response 20: Thanks for your comment. We have explained the effect of plastic deformation for material damage. The plastic deformation caused the honeycomb corrosion products to escape more easily from the radiation rod (in red).
Point 21: Provide more explanation on how the continuous etch pit formation process contributes to material damage.
Response 21: Thanks for your suggestion. We have provided explanation on how the continuous etch pit formation process contributes to material damage. The continuous etch pits were affected by the cavitation effect and the continuous impact of microjet, and fell off from the radiation rod, causing damage to the radiation rod (in red).
Point 22: Describe the differences in evolution processes of surface morphology between different roughness levels.
Response 22: Thanks for your comment. Descriptions of the differences in evolution processes of surface morphology between different roughness levels are added in Figures 5, 6, and 7 (in red).
Point 23: Clarify the significance of identifying TiAl3 as the corrosion product.
Response 23: Thanks for your comment. This paper only identifies corrosion products and studies corrosion mechanisms. This paper can provide an insight to develop a new homemade Ti alloy radiation rod with better resistance to corrosion in the ultrasonic melt processing (in red).
Point 24: Elaborate briefly on the role of TiAl3 in the corrosion process.
Response 24: Thanks for your comment. Titanium alloy radiation rod corrodes in aluminum melt and TiAl3 is generated at Al/Ti interface. This paper aims to explore the corrosion mechanism of radiation rod with different roughness under ultrasonic action. A portion of TiAl3 adheres to the radiation rod, forming a layer of protection to prevent the continued generation of corrosion products. Part of them enter the aluminum melt. A small amount of TiAl3 as the reinforcing phase is beneficial for the melt. However, a large amount of TiAl3 is harmful to the melt.
Point 25: Proofread the manuscript for minor grammatical errors and sentence structure issues.
Response 25: Thanks for your suggestion. We have carefully reviewed the sentence structure and grammar (in red).
Point 26: Ensure consistent use of units, especially when presenting experimental data.
Response26: Thanks for your comment. We have ensured consistent use of units (in red).
Point 27: Add recent literature such as: 10.1088/1742-6596/2267/1/012079, https://doi.org/10.3390/app13020730.
Response 27: Thanks for your suggestion. We have added reference [31,32] (in red).
Author Response File: Author Response.docx
Reviewer 3 Report
General comments
The submitted manuscript is aimed at studying the mechanism of corrosion damage caused by cavitation, using titanium alloy as a case study.
The topic is interesting and worthy of investigation, and it matches with the aim and scope of Coatings. However, major revisions have to be applied, sicne the collected results have been well described, but should be better discussed and compared with literature.
More details and specific remarks and suggestions are reported below point by point.
Abstract
- Please, add a contextualization before the description of the manuscript content.
Keywords
The chosen keywords (i.e. radiation rod; surface roughness; cavitation corrosion; cavitation collapse; TiAl3) have to be reported in a more logical order (i.e. materials, processing, characterisations, properties, applications).
Introduction
- The Introduction section is well conceived and the aim and originality of the submitted manuscripts have been well highlighted.
- It is suggested to add, at the end of the Introduction section, a list of the performed characterisations.
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2. Experimental details
2.1 Materials
- What was the alloy supplier?
2.3 Microstructural characterization
- More details about the microhardness measurements have to be added, such as the applied load, the time, the used indenter, the number of samples, the number of measurements for sample.
3. Results and Discussion
As a general consideration, the Authors should more deeply discuss the acquired data, comparing them with the literature. They well and deeply described them but they completely failed in comparing them with literature.
3.1. Weight loss rate
- The equation for the weight loss rate has to be moved to the Experimental section.
The quality of English language is good.
Author Response
Point 1: Please, add a contextualization before the description of the manuscript content.
Response 1: I’m so sorry for this point. There is very little literature on cavitation corrosion of ultrasonic rods used in melt casting, so we have not been able to find relevant literature. In the introduction, we introduced the application background, technical methods, blind spots in current research, main work we have done, and the significance of studying this work in sequence. Thank you again for your suggestion.
Point 2: The chosen keywords (i.e. radiation rod; surface roughness; cavitation corrosion; cavitation collapse; TiAl3) have to be reported in a more logical order (i.e. materials, processing, characterisations, properties, applications).
Response 2: Thanks for your suggestion. I have adjusted the order to “radiation rod; TiAl3; surface roughness; cavitation collapse; cavitation corrosion”(in red).
Point 3: The Introduction section is well conceived and the aim and originality of the submitted manuscripts have been well highlighted.
Response 3: Thank you for your recognition.
Point 4: It is suggested to add, at the end of the Introduction section, a list of the performed characterisations.
Response 4: Thanks for your comment. We have rewritten the third paragraph of the introduction (in red).
Point 5: What was the alloy supplier?.
Response 5: Thank you for your suggestion. 2A14 aluminum alloy is an aluminum alloy with a nominal composition of Al-0.90Si-4.20Cu-0.45Mg-0.11Zn-0.67Mn-0.10Ti-0.10Ni-0.050Fe (wt%) [34] (in red).
Point 6: More details about the microhardness measurements have to be added, such as the applied load, the time, the used indenter, the number of samples, the number of measurements for sample.
Response 6: Thank you for your suggestion. The microhardness tester (HV-1000A) with diamond indenter was used to measure the original surface microhardness of the sample. The sample size was 10 mm×10 mm×2 mm. Standard loads of 1.5 N was added. The operation time was 2 s. The microhardness values were obtained based on five different positions whenever possible (in red).
Point 7: As a general consideration, the Authors should more deeply discuss the acquired data, comparing them with the literature. They well and deeply described them but they completely failed in comparing them with literature.
Response 7: Thank you for your suggestion. This article mainly studies the corrosion morphology, weight loss, and reaction layer of different surface roughness. Due to my current level of proficiency, I have not been able to access reports on the impact of different surface roughness on the ultrasonic corrosion process, so it is impossible to compare the research results with those reported in the literature. In response to your suggestion, I will continue to study and delve deeper in the future, striving to make better research. Thank you again for your suggestions and corrections.
Point 8: The equation for the weight loss rate has to be moved to the Experimental section.
Response 8: Thank you for your suggestion. The equation for the weight loss rate has to be moved to the section 2.2 sample preparation (in red).
Author Response File: Author Response.docx
Round 2
Reviewer 3 Report
General comments
One minor revision has to be applied.
Abstract
- A contextualization before the description of the manuscript content was not added, as requested in the first revision. The Authors do not have to introduce something from Literature, but to introduce the problematic.
The English quality is good.
Author Response
Point 1: A contextualization before the description of the manuscript content was not added, as requested in the first revision. The Authors do not have to introduce something from Literature, but to introduce the problematic.
Response 1: Thanks for your suggestion. We have made corresponding explanations and introduced the problematic in the introduction. The references [25, 26] were also added. Reference [26] is a Chinese invention patent. We have rewritten the second paragraph of the introduction. The section modified to ”The above research had proven the effectiveness of ultrasound on the melt and also ignored the effect of corrosion of ultrasonic rod. The radiation rod used for ultrasound was damaged due to the influence of ultrasonic cavitation performance during actual work [25, 26]. The main reason for the damage of radiation rod was cavitation corrosion. On the one hand, cavitation corrosion reduced the service life of radiation rod; On the other hand, the corrosion products generated were harmful to the performance of the alloy. These were important reason limiting the popularity of ultrasonic casting industry. Titanium alloy has excellent physical and chemical properties compared to other materials [27]. Therefore, it was necessary to study the cavitation corrosion mechanisms of the titanium alloy radiation rod. The study of cavitation corrosion mechanisms has guiding significance for later corrosion protection [28, 29].” (in red)
Author Response File: Author Response.docx
