Compound Casting of Aluminum with Sheet Steel in 3D Sand Casting Using an Inductive Heating System

Round 1

Reviewer 1 Report

The present work entitled " A Compound Casting of Aluminum with Sheet Steel in 3D Sand Casting Using an Inductive Heating System " describes the mechanical properties and microstructure of the cast aluminum and sheet steel joints obtained by a novel 3D casting process using an inductive heating system. This topic is interesting and worthy to be investigated. The paper is generally well written, with a rather informative introduction. The conclusions are consistent with the evidence and arguments presented. The references are appropriate. The experiments were well designed. I think this paper can be considered for publication, but it needs some improvements. In my opinion, a characterization of the structure and composition of the joint zone from the point of view of the formation of intermetallic phases are not sufficiently described by EDS, XRD, SEM. Also, the structure of the joint zone could be better described with EBSD maps. In this case, it is possible to have information’s concerning the grain shape and size. This will contribute to obtaining strong conclusions and highlights of work.

Author Response

Dear reviewer 1,

 

thank you very much for your time and comments on the manuscript.

 

In the following I would like to respond to your comments.

 

 

1. Why could we not detect the three narrow phases (3/4/5) in terms of elemental composition?

Because the lateral resolution of our EDX is too low to measure the narrow phases with a size smaller than 1 or 2 µm. A better resolution can be achieved through special equipment or a better EDX. Unfortunately, we do not have this equipment, which limits the identification of the three phases within the scope of our technical possibilities.

But there is a similar publication which describes the same issue (“Sn-Aided Joining of Cast Aluminum and Steel Through a Compound Casting Process” from Bakke et al. https://doi.org/10.1007/s11663-021-02329-w page 63 paragraph 2 and Figure 3 (b).

However, the following assumptions can be made for phase determination through literature comparisons.

 

2. Which phases can be assumed?

The work of Bakke et al. shows that the SEM image in Figure 3 (b) looks the same like the one in our work, and the narrow phases could also not be detected by the EDX. The authors in the above article assume that these are Tau11 and an eta phase. Further work is needed to be carried out to determine the composition.

 

3. why didn't we do XRD, EBSD, SAED, TEM, STEM etc.?

Because we don't have the resources.

 

4. What changes have been made in the presented article compared to the previous version?

The findings of Bakke et al. were added on page 13. Lines 368-376 have been edited.

 

The current version is attached. Please note that suggested changes by other reviewers have also been incorporated by the author.

 

kind regards

Christopher Locke

Reviewer 2 Report

Please find below my comments, suggestions, and concerns:

Line 106. In the sentence “an uncoated DC04 steel sheet was used to measure the heating behaviour”. Why this material is different from the HX340LAD? In other words, why not to use the HX340LAD steel for tracking down the heating behavior?

In Figure 2. It should be “Ablation” instead of abliation line.

Line 169. Should not be “half mould” instead of “mould half”. Please check.

Line 173. Should not be “300 ppm?” instead of “300 ppmw”.

Line 261. In the sentence “is discussed in chapter 4”, correct to “is discussed in section 4”.

Line 262. maximum temperature?

Figure 5. Add a scale in one of the pictures or in a suitable location in order to provide clarity to the readership about the dimension of this. Please notice that this is important despite that the samples dimensions were already given in Figure 4.

Figure 8. In the legend, make more sense “Detailed View of Maximum Temperature: (a) Pyrometer measurement, and (b) Thermocouple Measurements.”

Lines 278-280. Why? commonly increasing the annealing treatment should decrease the strength but in benefit of increasing the ductility and elongation. Further explanation is required.

Lines 289-283. The relationship between the strength and grain size is well-know through the Hall-Petch relationship. Nonetheless, the ductility and elongation decrease must to be properly explained and support the arguments with the available literature.

Figure 13. Again, add the scale. Please notice that this is important despite that the samples dimensions were already given in Figure 4.

Line 326. The sentence “Each parameter combination was tested with three samples, Figure 15”. This sentence is somehow inconclusive or not properly elaborated. Please revise and rewrite properly.

Lines 336-336. In the sentences “The two specimens with laser surface engravings had a significantly lower maximum force of 8,3 MPa and 8,2 MPa compared to those without laser surface pre-treatment” two comments: 1) These values should be "8.3 MPa" and "8.2 MPa", and 2) in “compared to those without laser surface pre-treatment” where this statement can be seen in the Figure 15? In comparison with the literature, where these values fall? are these good values? extremely poor? please discuss this with the literature.

Line 345. what does it mean furan?

Lines 365-366. How do the authors identified the phases in the sentence " Number 1 resembles the Al4.5FeSi 365phase with a tongue-like morphology, and number 2 indicates the Al7Fe2Si phase" If the morphology is somehow known, references must be provided. On the other hand, EDS was not used, nor other chemical technique that help to elucidate these phases. Therefore, this should be explained in further detail or be more cautious with the affirmation of these phases.

Line 380. Section 3.2 instead of “Chapter 3.2”

Author Response

Dear reviewer 2,

 

thank you very much for your time and comments on the manuscript.

 

In the following, I would like to respond to your comments.

 

Line 106

• Line 106. In the sentence “an uncoated DC04 steel sheet was used to measure the heating behaviour”. Why this material is different from the HX340LAD? In other words, why not to use the HX340LAD steel for tracking down the heating behavior?
• response: The HX340LAD was coated and the DC04 was uncoated. In order not to influence the temperature measurement by the coating, DC04 was used. Also for the reason of availability, as the study has no external funding.

Figure 2

• In Figure 2. It should be “Ablation” instead of abliation line.
• response: abilation was replaced by ablation

Line 169

• Line 169. Should not be “half mould” instead of “mould half”. Please check.
• response: checked and corrected

Line 173

• Line 173. Should not be “300 ppm?” instead of “300 ppmw”
• response: corrected. 300 ppm it its.

Line 261

• Line 261. In the sentence “is discussed in chapter 4”, correct to “is discussed in section 4”.
• response: corrected

Line 262

• Line 262. maximum temperature?
• response: corrected to maximum temperature zone

Figure 5

• Figure 5. Add a scale in one of the pictures or in a suitable location in order to provide clarity to the readership about the dimension of this. Please notice that this is important despite that the samples dimensions were already given in Figure 4.
• response: scale is added

Figure 8

• Figure 8. In the legend, make more sense “Detailed View of Maximum Temperature: (a) Pyrometer measurement, and (b) Thermocouple Measurements.”
• response: all the temperature-measurement images were edited after commenting of a other reviewer

Lines 278-280

• Lines 278-280. Why? commonly increasing the annealing treatment should decrease the strength but in benefit of increasing the ductility and elongation. Further explanation is required.
• response: This is not the case due to the polymorphism of Fe.

 

Lines 289-283:

• Lines 289-283. The relationship between the strength and grain size is well-know through the Hall-Petch relationship. Nonetheless, the ductility and elongation decrease must to be properly explained and support the arguments with the available literature.
• response: The grain size influences the strength and the ductility. Small grains are more resistant to deformation by external forces since the dislocation is stopped at the grain boundary. Bigger grains lead to a decrease in strength and ductility.

Figure 13

• Figure 13. Again, add the scale. Please notice that this is important despite that the samples dimensions were already given in Figure 4.
• response: added a scale

Line 236

• Line 326. The sentence “Each parameter combination was tested with three samples, Figure 15”. This sentence is somehow inconclusive or not properly elaborated. Please revise and rewrite properly.
• response: rewritten to “ In Figure 15, the shear strength is plotted as a box-plot diagram. The bottom line represents the minimum value, the x represents the mean value, the top line represents the maximum value, and the line in the box represents the median value. For each parameter combination, three samples were tested.“

Lines 336

• Lines 336-336. In the sentences “The two specimens with laser surface engravings had a significantly lower maximum force of 8,3 MPa and 8,2 MPa compared to those without laser surface pre-treatment” two comments: 1) These values should be "8.3 MPa" and "8.2 MPa", and 2) in “compared to those without laser surface pre-treatment” where this statement can be seen in the Figure 15? In comparison with the literature, where these values fall? are these good values? extremely poor? please discuss this with the literature.
• response: 1) the values are checked. 2) Comparability between lasered and non-lasered samples is not given. For this reason, they are not shown in a diagram. Furthermore, only two specimens were subjected to laser processing. The strengths were compared and discussed with the literature in section 4.

 

Lines 345

• Line 345. what does it mean furan?
• response: furan is a organic compound used as binder to bound sand particles in the binder-jetting process

 

 

Lines 365-366

• Lines 365-366. How do the authors identified the phases in the sentence " Number 1 resembles the Al4.5FeSi 365phase with a tongue-like morphology, and number 2 indicates the Al7Fe2Si phase" If the morphology is somehow known, references must be provided. On the other hand, EDS was not used, nor other chemical technique that help to elucidate these phases. Therefore, this should be explained in further detail or be more cautious with the affirmation of these phases.
• response: The phases were determined using point EDX and compared with the literature. The section was rewritten accordingly.

 

Line 380

• Line 380. Section 3.2 instead of “Chapter 3.2”
• response: checked

The current version is attached. Please note that suggested changes by other reviewers have also been incorporated by the author.

 

 

kind regards

Christopher Locke

 

 

 

Reviewer 3 Report

The manuscript presents an attempt to link steel and aluminum plates through casting.

I don't think this super-complex linking method has any practical applicability. In fact, it is much more complex than using glue and the bond strength is lower.

The manuscript is very well written and understandable, and given that at the level of experimentation it is acceptable to try new things, I suggest its publication.

In the annex I indicate small notes to the care of the author.

Comments for author File: Comments.pdf

Author Response

Dear reviewer 3,

 

thank you very much for your time and comments on the manuscript. Based on the comments, the indicated sections are adjusted. These were as follows:

 

• 95 – 96:
  • your comment:

highlighting is integrated

• my response:

changed one of the words “integrated” into “implemented”

• 210:
  • your comment:

and shims of the same thickness as the adherent ones were placed to minimize the effect of the bending moment, right?

• my response:

Yes, the bending was minimized through adjustable clamps. The sentence is adjusted to: ”It is ensured that the clamping length was the same on the cast and the sheet side and that the bond zone was perpendicular to the tensile axis through adjustable clamps.”

• 257:
  • your comment:

it is more enlightening to say that this is an enlargement of the graphs 6 in the initial part

• my response:

Implemented your proposal: Figure 7 shows a detailed enlargement of Figure 6 of the initial part.

• 262:
  • your comment:

it is more enlightening to say that this is an expansion of graphs 6 in the maximum temperature zone

• my response:
  Implemented your proposal: Figure 8 shows an expansion of the graphs of Figure 6 in the maximum temperature zone.

• 275:
  • you comment:

it is more enlightening to say that this is an enlargement of the graphs 6 in the initial part

• my response:
  Implemented your proposal: Enlargement of the Graphs in Figure 6 in the initial part: …

 

• 277:
  • your comment:

it is more enlightening to say that this is an expansion of graphs 6 in the maximum temperature zone

• my response:
  Implemented your proposal --> Expansion of the Graphs in Figure 6 in the Maximum Temperature Zone: …

• 304-305 and 312:
  • your comment:

check repetition

• my response:
  checked repetition and deleted the repetition in 304-305

The current version is attached. Please note that suggested changes by other reviewers have also been incorporated by the author.

 

 

 

kind regards

Christopher Locke