Temperature Gradient and Solidification Rate Simulation Model of the Microstructure of Laser-Cladded 27SiMn
, Natarajan Jeyaprakash 1, Jiali Zhou 1, Yixing Wan 1 and Wenhui Yang 1
Round 1
Reviewer 1 Report
A very good work was done on "A Temperature Gradient and Solidification Rate Simulation Model of the Microstructure of Laser Cladded 27SiMn "
Methodology is good.
Language is good
Results and discussions were written well
Accept in its present form
Author Response
Referee: 1
No comments.
Thank you for accepting the manuscript in its present form.
Reviewer 2 Report
In submitted manuscript the authors analyzed the 27SiMn was selected as a substrate, and the powder was a self-made iron-based alloy.Additionaly, the thermophysical properties of the material were predicted by the CALPHAD phase diagram algorithm where the agreement between the results from the model calculations and the experimental results was 92%. The energy distribution in the laser cladding process analyzed by them, it was found that about 10% of the laser energy was used to heat the substrate to form a melt pool, and at least 53% of the energy was radiated into the environment. They analysed the effects of temperature gradient and solidification rate on the microstructure of the cladding layer were explored. The stated that numerical simulation results is helpful to predict the solidification rate, temperature distribution and microstructure of the melt pool, thereby reducing the cost of testing.
The submitted manuscript it is interesting but needs to be supplemented some issues.
1. The introduction is too general. There are few reports from the literature analysis.
2. Datas presents about the thermophysical properties of substrate and powder on Figure 1 are from some publication, own research whether producent. It is not clearly emphasized.
3. Please explain in more detail why such a steel substrate and such a powder were chosen?
4. In the paper, I miss the pictures of the track microstructures in relation to the simulation presented in Figure 5. The authors mention deviation region, and here they do not show pictures with such a phenomenon.
5. Figure 8 shows the cladded track diagram. Where are the trace microstructures from the experimental part?
6. The graph in Figure 8 is well known. The added microstructures are of poor quality.
7. Figure 11 looks like a scan from some book. Please correct it. Please justify its placement in this publication in more detail. These drawings are widely known.
8. The submitted manuscript is interesting, but requires a clear presentation of simulation and experimental results. I propose to present some comparisons in the table.
Author Response
Referee: 2
Comment 1: The introduction is too general. There are few reports from the literature analysis.
Responses: Thank you for the comment. As directed by the reviewer, the literature related to laser cladding with numerical simulation are included in the revised manuscript in section 1, line 37-55. The included content is given below for your reference.
Zixin Deng et al. [6] carried out the simulation model for laser cladding process to analyze the HA-Ag ceramic coatings. The solidification rate and corresponding temperature gradient were considered in the simulation process. The result revealed that the simulation results were well matched with the optimized laser process parameters. Chuanyu Wang et al. [7] investigated the solidification of molten pool and its thermal behavior during the fabrication of Inconel 718 through the laser cladding process. In this study, the solid-liquid transformation and heat capacity were considered in the simulation process. The velocity field and temperature distribution across the molten pool were analyzed. Qi Zhang et al. [8] performed the single and multi-track laser cladding on the Fe-Mn-Si-Cr-Ni alloy coating. The finite element analysis of the molten pool was carried out to evaluate the temperature distribution and corresponding induction of stress field. The simulated result revealed that the residual stress at the longitudinal direction was higher than the transverse direction. The tensile-compression-tensile distribution of the stress in the multi-track laser cladding process was found with the maximum peak temperature of 2600 . Qing Chai et al. [9] studied the mechanical property of Stellite6 which was fabricated using ultrasonic assisted laser cladding process. The temperature distribution field was analyzed numerically as well as the experimentation. The error between the experimental and simulated results were less than 10 % which confirmed the accuracy of the temperature distribution field.
Comment 2: Datas presents about the thermophysical properties of substrate and powder on Figure 1 are from some publication, own research whether producent. It is not clearly emphasized
Responses: Thank you for the comment. The thermophysical properties of substrate and powder on Figure 1 were obtained from the present research work. As suggested by the reviewer, the details are included in the revised manuscript in section 2.1.1, line 103-106. The included content is given below for your reference.
The thermophysical properties of the substrate and powder were obtained through the calculation with the support of CALPHAD phase diagram method and the corresponding results are shown in Figure 1.
Comment 3: Please explain in more detail why such a steel substrate and such a powder were chosen?
Responses: Thank you for the comment. As directed by the reviewer, the detail explanation for the selection of steel substrate and a powder simulation are included in the revised manuscript in section 2.1.1, line 87-98. The included content is given below for your reference.
In this study, 27SiMn was used as the substrate which was the main material of the domestic hydraulic cylinder. This substrate material encountered severe wear during its service in the harsh environment. It inevitably caused defects, namely scratches, voids, cracks and shallow pits on the substrate surface. As a result, the service life of the compo-nent reduced. The damage components were repaired with the use of different powders. The iron-based alloy powder with a particle size distribution of 20-53 μm was used as the cladding material, which has a good wear resistance, corrosion resistance and excellent machining properties [13]. In addition, the fluid phase temperature and the expansion co-efficient were similar to that of 27SiMn. Among the available different manufacturing techniques, the laser cladding process possessed higher efficiency, precise control of the layer thickness, superior bonding strength of repairing region with the substrate and widely applicable process.
Comment 4: In the paper, I miss the pictures of the track microstructures in relation to the simulation presented in Figure 5. The authors mention deviation region, and here they do not show pictures with such a phenomenon
Responses: Thank you for the comment. The authors agreed with the reviewer’s point of view. The track microstructure was not included due to the limitation of number of images. In future work, the authors are planning to study the deviation region separately, in which, we will include the all-relevant images.
Comment 5: Figure 8 shows the cladded track diagram. Where are the trace microstructures from the experimental part?
Responses: Thank you for the comment. We apology that the experiment part of cladded track was not given in Figure 8. Because, the experimental part of cladded track and its higher magnification images were given in Figure 13.
Comment 6: The graph in Figure 8 is well known. The added microstructures are of poor quality.
Responses: Thank you for the comment, Professor. Based on the reviewer comments, authors are tried and given the improved figures in the revised manuscript.
Comment 7: Figure 11 looks like a scan from some book. Please correct it. Please justify its placement in this publication in more detail. These drawings are widely known.
Responses: Thank you for the comment. As directed by the reviewer, the Figure 11a is removed in the revised manuscript. The Figure 11b is retained as the reader can easily assess the angle between the normal vector of the solidification interface and the scanning speed direction on the vertical plane. In addition, minimum angle, the maximum angle and the projection diagram of the solidification interface on the melt pool can be understand from the Figure 11b.
Comment 8: The submitted manuscript is interesting, but requires a clear presentation of simulation and experimental results. I propose to present some comparisons in the table.
Responses: Thank you for the comment. As suggested by the reviewer, the comparisons between the simulation and experimental results were included in the revised manuscript as Table 4 in page no 17.
Author Response File: 
Author Response.pdf
Reviewer 3 Report
- row 185 - what does the word "fig" mean?
- in all texts correct the units to say (for example) m.s-1, ... not m/s, ...
- please, when you write the formulas, put the unknown variable that the formula describes, solves, in the opening sentence, for example, row 197 "The concentration of the powder flux "C" in the space is" ....
- please improve the quality of the description of the images, for example Fig. 8 (Height), Fig. 9 - font in the diagram
Author Response
Referee: 3
Comment 1: row 185 - what does the word "fig" mean?
Responses: Thank you for the comment. The “fig” was unknowingly inserted in the manuscript. This word is removed in the revised manuscript from the row 185.
Comment 2: in all texts correct the units to say (for example) m.s-1, ... not m/s, Responses: Thank you for the comment. As suggested by the reviewer, the format of units are corrected throughout the manuscript.
Comment 3: please, when you write the formulas, put the unknown variable that the formula describes, solves, in the opening sentence, for example, row 197 "The concentration of the powder flux "C" in the space is" ....
Responses: Thank you for the comment. As directed by the reviewer, the unknown variable are inserted at end of the corresponding description and corrected throughout the manuscript.
Comment 4: please improve the quality of the description of the images, for example Fig. 8 (Height), Fig. 9 - font in the diagram
Responses: Thank you for the comment. As suggested by the reviewer, the quality of the description of the Figure 8 and 9 are improved.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
The authors included responses for my comments. I accepting the manuscript in present form.
