Effect of Ru on Deformation Mechanism and Microstructure Evolution of Single-Crystal Superalloys under Medium-Temperature and High-Stress Creep

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Deformation Mechanism and Microstructural Evolution during  Medium Temperature High Stress Creep in Ru-free and Ru containing Single-Crystal Superalloys

·       English error should be corrected.  For example:’…to produced..’ in the abstract. 

·       Please explain strain incubation in the abstract.

·       Abstract and introduction:’…at medium temperature and high stress creep..’:  please mention the temperature and the stress range.  The objective of the study must be strong. 

·       Please insert a schematic diagram of heat treatments.   

·       Figure 2 should be better.  A Table can be used for listing partition coefficient. 

·       “Figure 3d depicts the creep curves of 0Ru and 3Ru alloys at various temperatures and 168 stress levels (900^oC/320 MPa).”:incorrect.

·       Figure 3, Figure 4, Figure 5 and Figure 6 should be correlated.

·       The difference in deformation mechanism between  Ru-free and Ru containing single crystal superalloys can be illustrated and discussed well.   

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This work basically studies the effect of Ru element on γ' phase evolution and the deformation mechanism in Ni-based single crystal superalloy. The authors put a lot of emphasis on the creep mechanism of Ni-based single crystal superalloys by comparing the effect of Ru addition with Ru-free alloys under different temperature and stress creep conditions.

It is clear from the manuscript that a lot of work was invested in this research, however my opinion is that the real novelty of the research is missing comparing with the literature. Several paper can be found, what already deal with the creep mechanisms of the Ni-based single crystal superalloy. Accordingly, I also missed much more relevant literature in the introduction part.

Apart from that, the manuscript contains several grammatical and spelling errors, which make the manuscript very unprofessional. Just a few non-exhaustive examples:

The use of abbreviations is not consequent.

Line 47 and 50: The abbreviations are not explained in the correct place e.g. single crystal superalloy

Line 94:  The of explanation of EMPA is not correct.

Line 98: Title of the paragraph 3. 1. is wrong. What is Superalloy Alloy?

line 60: The nomination of 0wt% and 3wt% Ru content alloys is not consistent throughout the manuscript.

Line 93: Somewhere they introduce abbreviation e.g., air cooling (AC), single crystal (SC), but it is not used later in the text.

In the Figure 2., the axis inscription is missing.

The Fig. 7. a and b show the same images.

According to the quality of the journal of Materials, this manuscript contains significant shortcomings, therefore it cannot be accepted for publication in this form.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Thanks for the response from the authors! The manuscript underwent significant changes, which resulted in an increase in the scientific level of the work. Therefore, the revised manuscript is accepted in this journal.