Thermal Stress Cycle Simulation in Laser Cladding Process of Ni-Based Coating on H13 Steel
Round 1
Reviewer 1 Report
Abstract should avoid giving specific numbers and focus on facts that can be learnt from the study. Detailed numbers should be explained in the results parts.
There are some parts in the article like line 22 or line 240, where the Word "maximum" should be added to thermal stress, to clarify it.
Along the experiments there is a generalized omission of the time where the values are given (eg. you could use a time scale based on the moment before and after the laser spot center has irradiated the central point).
Figure 3 (right) is not easy to understand.
Figure 6 may be zoomed so the important part where the laser spot is, could show relevant information. These images do not show relevant information as such.
New figures from the model could be selected to offer more relevant information.
Please, detail what do you mean in line 149. The meaning can not be properly understood.
Author Response
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Reviewer 2 Report
75 % of the abstract contains the conclusions. It needs to be rewritten to have the contents one expects from an abstract.
If a H13 steel part needs to be repaired normally it is done with H13 steel too. The authors use Ni60 alloy instead which is not useful in practice. It is valid for the modelling, not as a real application-
Maybe the sentence “But the research on thermal stress and thermal cycle is rarely reported” is not hundred per cent true: there are papers published with multiple track laser cladding almost ten years ago.
The laser distribution used looks like Gaussian rather than planar, as the authors claim. This needs some explanation. The handling of the laser energy deposited needs also a more clear explanation: what is the incident angle in any portion of the track which is not flat. Depending on that, what is the absorbed fraction?
Heating and cooling speeds are better expressed in terms of K/s.
Linear dependence of temperature with laser power, keeping constant the rest of parameters, is quite an obvious property. Laser scan speed is chosen quite low, consider the experimental standards which are around 10 mm/s.
In the first six points, the valley between the peaks is connected with the modelling of the molten pool. The authors have to explain how the model works above the melting temperature. May be after the second peak the Von Misses stresses decrease too much.
Authors do not explain the source of thermophysical properties used.
Model validation with experimental data needs the use of an absorption coefficient: what is the value used in this paper?
Author Response
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Please see the attachment.
Thank you so much for your reviewing.
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Author Response.docx
Reviewer 3 Report
The paper is an interesting study of the basic processes and phenomena during laser cladding by using the numerical simulation. It tries to explain exact mechanism of creation of coating made from powder partially melted by laser. It shows how the junction between the cladding and the substrate arises and what stresses in the cladding can be expected. The model is carefully calculated and successfully compared to a real experiment. However, there is a number of mainly language issues, that has to corrected before the paper can be published.
Generally, language checking by a native English speaker would be recommended. I try to point out at least the clearest recommendations:
lines 11-14: The first sentence of the Abstract is very long and very soon starts to be clumsy. I recommend to divide it to two sentences.
line 37: 'hot extrusion dies and forging dies' -> 'hot extrusion and forging dies'
l. 38: 'high heating temperature' -> 'high temperature'
l. 47: last word 'and' -> 'while'
l. 58: 'But' -> 'However,'
l. 59: 'COMSOL has its own modeling tool for modeling.' -> 'COMSOL has its own tool for modeling.'
l. 78: 'more used.' -> 'used more' OR 'more popular'
l. 86-88: 'According to the chemical composition of the matrix and powder, select the corresponding material from COMSOL material, and use the physical properties of the material provided by the software.'
CHANGE TO
'According to the chemical composition of the matrix and powder, the corresponding materials from COMSOL database was selected, and their physical properties provided by the software were used.'
page 4:
The letters in Fig. 3 are very poorly visible, they are small and of bad color.
There is no reference to Fig. 3 in the text.
There is NO Figure 4. Neither is there a reference to it.
l. 114: 'COMSOL to solve' -> 'COMSOL solution'
l. 117: 'cladding surface, and the laser' -> 'cladding surface, while the laser'
l. 118-122: very long sentence, confusing, please reformulate
l. 132/135: It is not very clear how Fig. 5 shows the center and sides of the laser beam - it would be better if the y-axes of all plots showed the same values. Then in Fig.4b it would be very clear that T is higher. Also the lettering is quite small.
l. 158: 'were called out' - what does it mean?
l. 169: 'sample point 1-5' -> 'sample points 1-5'
l. 171: 'sample point 6 and 7' -> 'sample points 6 and 7'
l. 172-175: Question: Does the melt not wet the powder underneath? Does the model take that into account in any way?
l. 194: 'mpa' -> 'MPa'
l. 198: 'FIG. 8' -> 'Fig. 8'
l. 210: 'mpa' -> 'MPa'
l. 226: 'Conslusions' -> 'Conclusions'
l. 242-251: The last (3) point of Conclusions is poorly formulated and seems somewhat repeat the same ides. Please, reformulate the paragraph to better explain the points.
Author Response
Dear sir/madam,
Please see the attachment.
Thank you so much for your reviewing.
Round 2
Reviewer 1 Report
Current changes help to understand the experiments done.
Author Response
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Reviewer 2 Report
The paper deals with the Thermal Stress Cycle Simulation and the only validation is thermal. Authors only predict the depth of melting zone and, from that, you consider that the model is assessed also for thermal and residual stresses. Authors do not center the analysis in the relevant problems of laser cladding concerning thermal and resisual stresses. From my point of view, there are still work to do to reach the significant contribution expected from a scientific article
Author Response
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Reviewer 3 Report
The paper has been improved, the authors addressed essentially all the issues.
There are just two minor suggestions:
1. line 51: "not so much reports" -> "not so many reports"
2. Concerning Fig.5.: I understand now, that the original presentation was actually better since now the lines corresponding to the point 10 and 11 coincide and are not well visible. So, authors can use the previous plots.
However, I still think that it would be better if the scales on the y-axes were the same in all 3 plots - say from 600 C up to 2000 C. In this way the reader at a first glance can appreciate the temperature differences.
Other than that, the paper can be published basically as it is.
Author Response
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This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
