Bainite Transformation-Kinetics-Microstructure Characterization of Austempered 4140 Steel
Round 1
Reviewer 1 Report
Dear authors,
Subject of your paper is very interesting and steels with bainitic microstructure are today most popular materials of investigation and optimisation of production technology parameters. You should always take into consideration possibility of application of your laboratory experiments in the industrial scale, e.g. very short time of heat treatment you applied in laboratory condition.....
In attached file I try to indicate corrections to make your paper more clear and understandable for readers. I suggest carrefully editing of English language and style.
Best regards
Comments for author File: 
Comments.pdf
Author Response
Dear sir,
Thank you very much for putting so much work in to provide revisions and corrections of my original manuscript.
Your effort is very much appreciated.
Please find the attached word file that I corrected and revised according to your directions.
I hope you can accept this revision, as I have put tremendous work in so far in this work, and try to do it with less mistake.
Thanks you very much.
Jian
Author Response File: Author Response.pdf
Reviewer 2 Report
This paper is showing semi-empirical model on bainite transformation kinetics of austempered AISI4140 steel using JMKA equation. This kind of work have been studied by many researchers before and there are nothing interesting. I could not find any originality and novelty in this paper. Introduction is too general to specify their aim to perform this work. It is insisted that they complete kinetics models on upper bainite, lower bainite, and martensite phases. However, they did not provide any evidence on each phase such as TEM micrograph, but just OM micrographs. It is general that transformation kinetics is measured by dilatometry experiment. However, they estimated transformation kinetics by measuring hardness. They should explain why hardness measurement is used and compare their result with dilatometry data to confirm reliability.
Author Response
Dear sir,
We have worked very hard on this study, hope you can reconsider your position because:
the bainite transformation kinetics and microstructures of the isothermal process on mixed structures as Upper/lower mixture or lower bainite/martensite structures or I mentioned as phase matrices were not carefully studied before, this study revealed some new details of all those aspects and some specific results were achieved. For a quick grasp of the bainite transformation characteristics, it is practical just to use OM micrographics and hardness measurement to understand the isothermal process's impact on the desired application, especially for industry quick prototype products making process. As today 's automotive industry demands a very short product development cycle. Bainite transformation activation energy was calculated using different methods, results are beneficial to the researchers since our study shows that K based method is preferable compared to the 1/t50 based methods, and the results aligned with many other published data.Round 2
Reviewer 1 Report
Dear authors,
Only selected suggestions and question I send you in the attached file. Most of my previous questions did not corrected.
I still suggest extensively correction of English language to make article more clear and understandable.
Best Regards
Comments for author File: Comments.pdf
Author Response
Dear Sir, again, thank you very much for your patient and effort in helping us improve this paper.
Dr. Prof. Barber, who is also one of the authors of this paper, is a native speaker of English, he reviewed this paper already.
Thank you again for the 2nd round review, I have done the following this round.
1) fixed the minor text errors as you pointed out.
2) redid most graphics to ensure legible when printing the paper in black and white.
3). revised the reference list as you directed.
I attached the tracked change file here.
Really appreciate your directions here.
Sincerely thanks.
Jian
Author Response File: Author Response.pdf
Reviewer 2 Report
Although the transformation kinetics modeling on the microstructures of bainites, martensite, and mixture of them during isothermal heat treatment is the main concern, it is necessary to make the microstructures clear by providing TEM images on upper/lower bainites, martensite, and mxture of them to give accurate information to readers. Do you have any reaseon why cannot you present TEM micrographs?
Author Response
Dear sir,
Thank you for providing directions here.
You are right it is better to do the TEM micrographs. Yet in our not so perfect conditions, it is a lot easier, quicker to just look the microstructures in LM.
TEM availability, sample preparation, and actual operations are not easy to come by.
In our automotive industry, quick and dirty prototype type work to provide product development is very practical to reduce the development cycle time, from this standpoint, our work will help for that purpose.
Thank you very much in advance for your understanding.
Sincerely yours
Jian
Round 3
Reviewer 2 Report
Even if several data are necessary to increase the quality of this paper, the results in this paper seem reasonable to publish.
