The Effect of Pre-Deformation on the Microstructure and Hardness of Al-Zn-Mg-Cu Alloy

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This study examines how hot rolling pre-deformation impacts the precipitation behavior of Al-Zn-Mg-Cu alloys, exploring the connections between deformation degree, dislocation density, and mechanical properties through various experimental techniques. Despite its potential, the manuscript faces several challenges that diminish its clarity, quality, and scientific significance.

1. The title lacks specificity and fails to highlight the study's unique aspects. The phrase "Research on" is overly broad and should be revised to better reflect the content.
2. The abstract is deficient in clearly stating the study's novelty, providing quantitative details, and offering a compelling conclusion. It should incorporate specific data points, emphasize the research's innovative aspects, and conclude with a strong statement on the findings' importance.
3. Essential experimental details are either missing or unclear, including the rationale for chosen rolling percentages and temperatures, as well as precise equipment settings for XRD and SEM analyses.
4. Several figures, particularly those related to hardness measurements (figures 7, 8, 9, and 12), are inadequately labeled, lacking error bars.
5. The discussion section requires expansion to include in-depth explanations of mechanisms, the implications of the results, and comparisons with existing research.
6. The explanation for changes in hardness and dislocation density is inadequate and insufficiently supported by data. A more comprehensive analysis of how deformation and aging influence hardness and microstructural properties is necessary.
7. XRD patterns and microstructure images are poorly elucidated, with weak connections drawn between these results and the study's conclusions. A clearer link between XRD and microstructural findings and their relationship to precipitation behavior and mechanical properties should be established.
8. The conclusion excessively repeats the results without addressing the broader significance or potential applications of the findings. It should summarize the most crucial insights, emphasize their practical implications, and propose directions for future research.

Author Response

Please see the attached file.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript is interesting and generally well-organized; however, a few clarifications should be made:

row 12 In the abstract specify that hardness was evaluated, since just mechanical property (and just one) doesn't sound right. 

row 107 to 110 I have seen this approach before. However, could you justify the removal of the highest or lowest values, even if they appear to be correct and without specific doubts? Please provide a reference to a statistical method that recommends this practice. Instead of eliminating certain values, readers might be more interested in the measurement error or standard deviation.

Does the grain size measuring formula require a reference? What about the second formula as well?

For Figure 7, consider using a larger scale on the y-axis, as all values seem to cluster around 90 HV. It is difficult to highlight the variations with the current scale.

Rows 201-205, a scientific explanation should be provided for the observed increases or decreases in hardness based on the rolling pressure. At the very least, include some comments or references for comparison. The changes in the microstructure may contribute to hardness increase, which warrants further discussion.

The description of the equipment and working parameters is vague. For instance, details such as loading/unloading times and the number of measurements taken in the same area need clarification. I understand that 30 measurements were made across 30 different zones, but one measurement in one area is precise?. What is the size of the tested sample?

The term "corrosion" may not be appropriate in the context of Keller's reagent; "etch" is more commonly used in this case.

The text in Figure 4b is difficult to read.

Carefully number the references; references 4 and 5 are actually one source, and reference 17 is incomplete.

Author Response

1. Please see the attached file.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

corrected.