Impact of Welding Parameters in the Porosity of a Dissimilar Welded Lap Joint of CP800-XPF1000 Steel Weldment by GMAW-P

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The research concerns an interesting topic. Text is effective, clear and well organized but need improvements. The abstract is correct, contains a summary, key findings, but need revision. However, the  Methodology is well described but also need revision too. It is possible to reproduce the tests carried out on the basis of the article. The conclusions are questionable, may need to be changed after more accurate data analysis. Few detailed comments have been presented described as follows:

+ Please revise the reference manager software, citations are missing in some parts of the manuscript (Error! Reference source not found.. ).

+ In materials and methods, please include an image of the Plates of 2.2..... Also, what are the applications of XPF1000 steel ?

+ What kind of steps use Taguchi's methodology?

+ Please, include details about the equipment used in OM and SEM. KeV, electrons, etc.

+ Any reference for (microstructure of CP800 steel characterized mainly by a ferrite matrix (F), up per bainite (UB), martensite island (M), and austenite retained (AR)). Also, discuss and compare with the open literature consulted. Figure 3.

+ Figure 1 text its hard to see.

+ From Figure 4, in the description a) and b) are not described correctly. In this way, how fig 4b was obtained.

+ Microstructural analysis require revisions. The analysis its poor.

+ Please include a scale bar in Figure 6.

+ Please discuss why the porosities are formed (physics) on the materials.

+ How many times the tests were replicated to guarantee the statistical significance.

+ Conclusions need to be rewritten.

+ DOE analysis with ANOVA is not provided. Please incorporate more information about the statistical analysis.

 

+  The introduction section intended to show (highlight) parts of the problem that are not solved by other scientists. - The outcome of the review is the identification of a “gap” of research that is not occupied by other scientists in this problem.

+  The conclusions are not aligned with the objectives. Therefore, it is necessary to clearly describe the purpose of the study so that the result points are the same as the conclusions.

+  Conclusions in accordance with the objectives set, however, it is desirable to expand the text in them.

+ The methodology, Methods, and Materials section must give a clear overview of what was done and give enough information to replicate the study (like a recipe!); be complete, but make life easy for your reader! break into smaller sections with subheadings, cite references for commonly used methods, and display a flow diagram or data table where possible. This section is missing.

+ Please, the authors needs restructure the paper because are not clear the typical structure of the paper.

Comments on the Quality of English Language

minor

Author Response

We attached a file with our response to Reviewer 1.

Regards,

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

 

This work investigates how welding parameters (frequency, peak current, background current, etc.) affect the porosity of a dissimilar welded lap joint CP800-XPF1000 steel. Welded joints were formed with various welding parameters and the phase constitution, porosity, and hardness of the joints were evaluated. The paper contains new results to merit publication. However, I have a few minor remarks to improve the paper.

 

 

1.     I am not familiar with the Taguchi methodology. I believe that there are few who are familiar with it. Some explanation and/or reference are recommended to be added.

2.     Several sentences are grammatically incorrect. For example,

“Careful was taken in order of do not touch the area to be tested with the chisel.” (line 120)

“Specifically with the use of the GMAW-P plays an important role, generates an undercooling that favours the rapid formation of grains…” (line 190)

Please reexamine the entire manuscript in light of the English usage.

3.     It is written that “Figure 3a shows the microstructure of CP800 steel characterized mainly by a ferrite matrix (F), upper bainite (UB), martensite island (M), and austenite retained (AR).” (line 127) However, in Fig. 3(a), only M, F, and B? are indicated. Do you mean “UB” by “U”? Where is AR?

4.     “14.61 and 1 micro-meter” (line 141) “0.73 micro-meter” (line 142)

How much are the significant digits?

5.     Figure caption of Fig.7 is insufficient. Similarly to Fig. 6 and 8, information on heat imput (250, 245, 238, or 236 J/mm) should be added.

6.     I think trial 1-4 in text correspond to experiment 1-4 in Table 4. If so, “experiment” in Table 4 should be changed to “trial”, or “trial” in text should be changed to “experiment”.

 

 

 

Comments on the Quality of English Language

As indicated above, please reexamine the entire manuscript in light of the English usage.

Author Response

We attached a file with our response to Reviewer 2.

Regards,

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Paper No.: metals-2866538

Title: Impact of the welding parameters in the porosity of a dissimilar welded lap joint CP800-XPF1000 steel by GMAW-P

There are some raised issues that should be treated.

1-     In lines 18-20: “In the case of a heat input higher than 0.30 KJ/mm generates up to 0.32% porosity in the weld metal, while a heat input lower than 0.25 KJ/mm generates up to 28% porosity in the weld metal”  I think 28% should be changed to 0.28%. Please revise.

2-      The literature review should be closed with the novelty, the need and the aim of this research.

3-      There is a bad cross linking of the figures’ and tables’ numbers in the text, so that this error appears “Error! Reference source not found”. Please treat it.

4-      The double fillet lap joints are more applied and more stable than the single fillet lap joints. Why the authors applied the single fillet lap joints?

5-     . What is the applied standard for the sample in Figure 1. Please use sub-figure numbers (a & b) for the images in Figure 1.

6-      In Figure 8: What are your evidences to propose the microstructural constituents (M, B, P & F). The magnification is not high enough to identify such constituents. Else, XRD has been conducted. The same valid for Fig. 7.

7-     Can XRD identify the mentioned intermetallic phases in Fig. 4.b?

Author Response

We attached a file with our response to Reviewer 3.

Regards,

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Both the quality of the research and the significant changes that the authors made to the article are very valuable. I think that the manuscript is suitable for publication. 

Comments on the Quality of English Language

minor

Author Response

We appreciate all your comments and recommendations to nurture and improve our manuscript.

Regards

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have not / well reacted to the following comments:

1- A heat input lower than 0.25 KJ/mm generates up to 28% porosity in the weld metal. It is not clear from the images that the porosity is 28 %. please revise.

12-       In Figure 8: What are your evidences to propose the microstructural constituents (M, B, P & F). The magnification is not high enough to identify such constituents. Else, XRD has been conducted. The same valid for Fig. 7.

23-      Can XRD identify the mentioned intermetallic phases in Fig. 4.b?

Author Response

 

1- A heat input lower than 0.25 KJ/mm generates up to 28% porosity in the weld metal. It is not clear from the images that the porosity is 28 %. please revise.

= Figure 6h with 0.236 J/mm show the result of radiography with the evidence of the heat input on the porosity.

 

12- In Figure 8: What are your evidences to propose the microstructural constituents (M, B, P & F). The magnification is not high enough to identify such constituents. Else, XRD has been conducted. The same valid for Fig. 7.

= We appreciate your comments. We did ott use XRD for characterization in this study, only EDS analysis. Figure 8 was developed and incorporated for explaining the different microstructures showed in the characterization evaluations. We added new images with higher magnifications as evidence.

 

23- Can XRD identify the mentioned intermetallic phases in Fig. 4.b?

= As previously mentioned, we did not use XRD for characterization in this study, only EDS analysis. We don’t have access to an XRD device.

 

Author Response File: Author Response.pdf

Round 3

Reviewer 3 Report

Comments and Suggestions for Authors

In Figs 6 & 7 , the subfigure character (a, b, c, ...) text size are not comparable with the manuscript text. Please modify.

Author Response

Thanks for your comments,

Both figures have been modified and updated in the main manuscript.

Regards,