Laser In Situ Synthesis of Gradient Fe-Ti Composite during Direct Energy Deposition Process
Round 1
Reviewer 1 Report
This article investigates the direct energy deposition (DED) process of Fe-Ti composites in metal additive manufacturing at different scales and in different modes. The possibility of preparing Fe and Ti bonds by DED is explored, and the structure of the prepared samples is investigated to reveal their structural characteristics and to propose the use of Fe-substrate for stress reduction.
The following suggestions are made.
1. the summary needs to be improved in the conclusion section.
2. The description of the echelon variation of the microhardness of the samples prepared by DED is not good enough, please add over more explanation.
3. It is mentioned in the article that the content of metal parts compounds can cause cracks, what are the causes? (local volume changes？stress changes?) Please further refine the causes of crack formation.
Overall Recommendation: Accept after Minor Revisions
Author Response
Response to Reviewer 1 Comments
- the summary needs to be improved in the conclusion section.
Response 1: The summary is improved with quantitative arguments from conclusion section - The description of the echelon variation of the microhardness of the samples prepared by DED is not good enough, please add over more explanation.
Response 2: On the page 5 description of the microhardness variation due to cracks and pores is added. - It is mentioned in the article that the content of metal parts compounds can cause cracks, what are the causes? (local volume changes？stress changes?) Please further refine the causes of crack formation. In the Response 3: Discussion section there is large description of cracks due to stress on the interfacial surface based on calculation of the continuity preservation condition (CPC) and the Crack initiation criteria CIC
Reviewer 2 Report
General comments：
1 Its better to provide the Fe-Ti phase diagram or cite references.
2 It is better to mark all phases in the SEM images for easy differentiation, such as dendrites, eutectic fragments, fibers….
3 It is recommended to give enlarge images of XRD patterns near angles of 45°, So that the reader can understand and distinguish these phases.
4 Line 218, it states, “modes 1 and 2 have the high level of noise and wide dispersion of interferences peaks, that is result of high level of residual stresses and disordering of crystal lattice structure.” Why is this case? Please clarify, if necessary, please cite to some references.
5 The whole manuscript should highlight the innovative and general applicability of DED Fe-Ti, especially for the abstract and conclusions.
6 Typographical errors: There are some minor grammatical errors and incorrect sentence structures. Please run this through a spell checker.
Author Response
General comments：
1 Its better to provide the Fe-Ti phase diagram or cite references.
Response 1: The reference 12 is added.
2 It is better to mark all phases in the SEM images for easy differentiation, such as dendrites, eutectic fragments, fibers….
Response 2: It require to wide figures or divide them on the several fragments. That can lead to cancel the connection between different parts of image and main idea of interpretation but does not give significant improving. Content of tables 2, 4 and 6 added with description of phases.
3 It is recommended to give enlarge images of XRD patterns near angles of 45°, So that the reader can understand and distinguish these phases.
Response 3: Figure 8 is added. It contains required information.
4 Line 218, it states, “modes 1 and 2 have the high level of noise and wide dispersion of interferences peaks, that is result of high level of residual stresses and disordering of crystal lattice structure.” Why is this case? Please clarify, if necessary, please cite to some references.
Responce 4: Cites are included.
5 The whole manuscript should highlight the innovative and general applicability of DED Fe-Ti, especially for the abstract and conclusions.
Response 5: Absract and Conclusion sections are improved with comments about applacability of DED technology for Fe-Ti composites.
6 Typographical errors: There are some minor grammatical errors and incorrect sentence structures. Please run this through a spell checker.
Response 6: The profreading is performed. A lot of mistakes are canceled.
Reviewer 3 Report
The current work presents the DED processing of the Fe-Ti FGM system. It is well known that this system is challenging to process as it forms several intermetallic phases that are hard and brittle leading to cracking. The authors present the same information again, which is a well-established fact. There is no new approach followed in the current, and even FGM is also a well-attempted route. The authors mentioned several microstructural attributes, but they are not clear from the micrographs presented.
Author Response
The current work presents the DED processing of the Fe-Ti FGM system. It is well known that this system is challenging to process as it forms several intermetallic phases that are hard and brittle leading to cracking. The authors present the same information again, which is a well-established fact. There is no new approach followed in the current, and even FGM is also a well-attempted route. The authors mentioned several microstructural attributes, but they are not clear from the micrographs presented.
Response: We are very gratefull for reading and crytical estimation of our work. We'll tried to account all comments during correction of the paper.
Round 2
Reviewer 3 Report
I could not find the specific replies to my comments.
Author Response
Please see the attachment
Author Response File: 
Author Response.pdf
