Calibration of Finite Element Model of Titanium Laser Welding by Fractional Factorial Design

Round 1

Reviewer 1 Report

1. Full name of HLFC should be given when it first appears. LBW, FEM , HAZ are the same, all abbreviations must be given full names when they first appear.

2. Table 1 was not mentioned in the text.

3. In page 6 line 151 ‘table 1’ here seems very strange.

4. In page 6 line 154 another table 1 appear.

5. In page 6 line 149 figure 6 appear twice.

6. Figures in the paper are not clear enough.

There are many low-level errors in this article. It is recommended the author read the full text and modify it.

Author Response

Dear reviewer, thank you very much for your comments. Please find attached a document with our responses.

Best regards

Author Response File: Author Response.docx

Reviewer 2 Report

Dear authors,

I am pleased to inform you that the review of the assigned manuscript was conducted.

Generally, the manuscript has several positive features. First of all, the purpose of the work was clearly stated. Secondly, the work was well organized, well discussed, and in most parts, well written (the English and syntax of the manuscript were satisfactory). And lastly, there is a range of good results and technical discussions in the manuscript. Accordingly, the manuscript has some important contributions to the advancement of knowledge in the area of laser welding.

Although the manuscript has high quality, there are some critical points that should be modified or clarified by the authors so that the manuscript may be deserved for publication in the Journal of Manufacturing and Materials Processing.

Reviewer’s comments

There are some technical errors and vague sentences in the manuscript which should be modified or clarified.

Technical comments:

- Line 156: An uncouple analysis of the welding process as sequential thermal transient and elastic-plastic analyses was carried out. The authors are asked to explain how they transfer the results from thermal analysis to mechanical (elasto-plastic) analysis (and vice versa)?

- Line 163: Which element in Abaqus was used for the thermal model? and which boundary conditions were applied?

- Line 200: In Abaqus software, it is not possible to apply non-uniform distributed thermal flux/loads such as cone heat flux as a function of coordinates (x,y,z). It is required to program subroutines DFLUX or DLOAD to apply such a load/flux (it needs coding).

How did the authors apply the cone-shape thermal load (and also considering the welding speed)? And why did not they explain it in the text?

- Line 237 and Eq. (7): The authors mentioned that “Because the reduced number of levels of the Fractional-Factorial Design, it is not possible to determine quadratic terms.” This means that the quadratic terms are eliminated from the regression model. If in reality, the nature of the conical Gaussian heat flux model depends on its quadratic parameters, the model obtained by the authors is not correct. How do the authors rebut this issue?

- Line 243: It is strongly recommended to write an optimization problem in a standard form. The authors can refer to Eq. (14) in the following paper to observe the standard format:

https://doi.org/10.1016/j.simpat.2020.102141   

- Line 255: In Table 5, for Case 8, T1 is 1212 ^oC. Does any phase transform occur in the material?

- Line 276: Which software was used to perform ANOVA?

- Line 278, Table 6: The p-value was only reported for objectives (outputs: T1-T4, ang), not for design variables (inputs: re, ri, yi, eff). The authors are requested to follow Table 7 in the paper below and write p-value for each term in the regression models.

In addition, what are the values of R2-adj? R2-adj is as important as R2 and should be reported. (e.g., see Table 7 in the paper below)

https://doi.org/10.1016/j.simpat.2020.102141   

- Line 289, Table 4: The desirability for T changes considerably, from 0.37 for T4 to 0.94 for T1. This is questionable because T1, T2, T3, and T4 are all of the same nature (temperature). Can the authors elaborate on this?

- Section “2.2. FEM model”: The input data into the FE model including mechanical, material, and thermal properties were not given in tabular forms in the manuscript (even though the references for properties were mentioned).  

- Section “2.2. FEM model”: There are several material constitutive models such as Johnson-Cook, Power law, and Zerilli-Armstrong for FE simulations of welding processes. The authors did not mention which constitutive model they utilized.

Grammar, vocabulary, and format comments:

- Line 2: The title of the manuscript looks grammatically awkward. The following title is suggested:

Calibration of Finite Element Model of Titanium Laser Welding by Fractional Factorial Design

Note: Welding is an uncountable noun.

- Line 9: The comma after the word “methodology” is redundant and should be removed.

- Line 21: What does HLFC stand for? It is required to be defined.

- Line 24: What does LBW stand for? It is required to be defined.

- Line 30: “into” should be replaced by “on”. Grammar: Focus something on something.

- Line 31: “because” should be replaced by “because of”.   

- Line 39: “are” should be inserted before “very time-consuming”.

- Line 45: “A considerable number …” is correct.

- Line 54: “Comprehensive literature reviews” is correct. (not “A comprehensive”)

- Line 55: Following the above correction, “were” is correct. (not “was”)

- Line 61: “in good agreement” is correct. “agreement” is uncountable.

- Line 69: What does TIG stand for?

- Line 77: “… simulated by taking into consideration thermal …” is correct.

- Line 89: “Inherent strain method, which is not included in this paper, was implemented” is correct.

- Lines 101: “… alloys, which makes it possible to obtain …” is correct.

- Lines 110, 281, 290, 293: “Error! Reference source not found” is not clear.

- Line 115: “… and software …” is correct. “software” is uncountable.

- Line 149: “figure 6” was repeated.

- Line 153, Figure 6: The titles of the X and Y axes are not written in the four diagrams?!

- Line 158: “because” was repeated.

- Line 164: “where” should be replaced by “were”.

- Line 196: “is being used” should be replaced by “has been used”.

- Line 200: “to optimize” is correct.

- Line 212: “parameters range” should be replaced by “parameters’ ranges”.

- Line 221: “There are techniques…” is correct.

- Lines 229: “The objective of RSM is to find the optimum working point using the minimum number of trials FEM models results (temperatures and distortions) are gathered after all cases are simulated.” The syntax of these sentences is not correct.

- Line 235: “due to” should be replaced by “because”.

- Line 247: “This study uses expressions proposed by Harrington [51] evaluate the overall response.” What is the subject of the verb “evaluate”? Probably, the authors meant:

This study uses the expressions proposed by Harrington [51] to evaluate the overall response.

- Line 265: “… the location of …” is correct.

- Line 301, Figure 10: The titles of the X and Y axes are not written in the four diagrams?!

- Line 310: “Figure 11” is correct. There is “Figure 10”.

- Line 310, Figure 10-a: Why are the X and Y axes the same?

In conclusion, If the authors apply the corrections to the manuscript, the manuscript will be suitable for publication in “Journal of Manufacturing and Materials Processing”.

Regards,

The reviewer

October 6, 2022

Author Response

Dear reviewer, thank you very much for your comments. They have been very useful for improving the manuscript. Please find attached a document with our responses.

Best regards

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

This paper can be accepted now.

Reviewer 2 Report

Dear Authors, 

Thanks for applying the comments including some revisions, equations and explanations essential for improving the quality of your research work.

The manuscript is currently suitable for publication in JMMP.

Regards,

The reviewer