Review Reports

Round 1

Reviewer 1 Report

Technical:

1. What is the sample utilized for tensile testing?  How many replicates were conducted?  Are the mechanical properties listed on Table 2 average values?  If so, what is the error? 
2. What is the basis of the selected ageing times and temperatures? 
3. For the same ageing condition, the sample to sample variation is high.  For example, the third peak displacement values for S1 and S4 samples range from 90 to 115 and 90 to 140 mm, respectively.  Why is there a huge variability?  How does this impact the modeling?
4. The authors claimed in Section 3.2 that the difference in the peak loads of the various samples are shown in Figure 3.  It is not clear as the curves are sitting on top of each other.  Consider replotting and including an inset. 
5. What is the the equipment's resolution limit for displacement?  Are the displacement values in Figure 6 (and in other figures) statistically different? Specifically, when the first three data points are within error of each other?
6. Is the material undergoing work hardening during the course of crush test, such that there is a dynamic mechanical property changes?  If yes, should these dynamic change be considered for Stages 3 and 4 modeling?
7. Will the model apply for samples with different dimensions (e.g. same base but longer extruded length or vice versa)? 
8. The verification sample has a UTS/YS lower than the training set.  Have the authors considered a validation sample in the upper end? 
9. How robust is the model relative to the range of tensile properties? or to other Al-Mg-Si alloys?  This has to be considered given the automotive industry does not only use a single alloy composition.   

Formatting:

1. Need dimension units for Figure 1
2. Correct reference formatting on the first two paragraphs of Section 3
3. Correct spelling of valley in Figure 4
4. Define Xp in Equation 4

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The reviewed manuscript is focused on the crushing and mechanical properties of KHC63 alloy samples. The results of theoretical calculations are supported by the experiment. The stages of the crushing process were analysed and well discussed. Developed physical model and mathematical relationship between crushing force and displacement can be of potential interest for the field. The manuscript looks constant and can be published after some minor improvements.

-Please check the wrong references on page 3.

-Please improve Eq. 11 and Eq. 12.

-Manuscript will benefit from providing the standard deviation data on the tensile properties

-Table 2 reports the measurements of 6 samples not 5 as stated in the caption

-Please check the S5 sample aging in Table 2

-I would also suggest adding some details into the introduction part concerning why there is a need to develop a new type of Al alloy and its difference from the commercial alternatives

-Figure 9 can be improved by modifying the y-axis scale to make curves

-References should be revised to add recent progress in the field.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

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