Considering the Effect of Non-Propagating Cracks on Fatigue Limit Prediction in the Critical Distance Method Framework
Round 1
Reviewer 1 Report
The paper discusses a model taking into the account the effect of non-propagating cracks on fatigue limit prediction. Critical distance method framework is considered. Authors propose to use non-propagating crack length and the conventional critical distance as a new critical distance (formula 9). Fatigue strength of notched specimens predicted by the proposed model is similar to predicted by other models (table 5 and fig. 11).
Some recent advances in analytical and experimental damage modeling for tribo-fatigue systems and new materials could be referred to in the paper:
(i) a method of experimental study of friction in a active system, (ii) state of volumetric damage of tribo-fatigue system, (iii) spatial stress-strain state of tribofatigue system in roll-shaft contact zone, (iv) modeling of the damaged state by the finite-element method on simultaneous action of contact and noncontact loads, (v) tribo-fatigue behavior of austempered ductile iron monica as new structural material for rail-wheel system, (vi) research on tensile behaviour of new structural material monica, (vii) measurement and real time analysis of local damage in wear-and-fatigue tests, (viii) modeling of volumetric damage of multielement clamp-knife-base tribo-fatigue system.
Style of references in the text like “Numerous evidence 22.)23.)24.)25.)26.)27.)28.)29.)30.)” should be corrected.
The paper “Considering the Effect of Non-Propagating Cracks on Fatigue Limit Prediction in the Critical Distance Method Framework” could be published in Applied Sciences after minor revision.
Author Response
Dear reviewer:
On behalf of my co-authors, we are very grateful to you for giving us the opportunity to revise our manuscript. We appreciate your positive attitude and constructive comments and suggestions on our manuscript entitled " Considering the Effect of Non-Propagating Cracks on Fatigue Limit Prediction in the Critical Distance Method Framework " ( ID: applsci-1981522).
We have carefully studied your opinions and tried our best to revise our manuscript according to the comments. The following are the responses and revision. I have answered your questions and suggestions on an item-by-item basis. We also attach the revised manuscript.
Comment 1: Some recent advances in analytical and experimental damage modeling for tribo-fatigue systems and new materials could be referred to in the paper.
Response: We admire your broad insight in material fatigue. We also notice the application of the critical distance method in friction fatigue. For this reason, a literature on friction fatigue is added to the introduction of our manuscript. The label of the literature is [12].
Comment 2: Style of references in the text like “Numerous evidence 22.)23.)24.)25.)26.)27.)28.)29.)30.)” should be corrected.
Response: Thanks for the reviewer's reminder, we have carefully revised the style of references.
We would like to thank the reviewer again for taking the time to review our manuscript.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Comments on the paper
1. Page 3, line 3b, 2b - is Fi. 4 and Mpa a should be Fig. 4 and MPa.
2. In Fig. 3 you can see some sample devices mounted, it would be good to describe them in the text.
3. Fig. 4 - no scale in the drawing.
4. The question is what is the fracture length in Fig. 4b? There is propagation, it can be seen, only in terms of short or long cracks?
5. In the caption Fig. 4 there is no caption for a) and b).
6. On Figs. 5, 8, 10, 11 and parts in the whole work we have Mpa, and it should be MPa.
7. Very little information on FE modeling itself.
8. It would be worthwhile to quote in the introduction also papers of: 1) J. Lewandowski, D. Rozumek, Fatigue crack growth in welded S355 samples subjected to bending loading. Metals, Vol. 11, 1394, 2021, 2) D. Rozumek, Z. Marciniak, Fatigue properties of notched specimens made of FeP04 steel. Materials Science, Vol. 47, No. 4, 2012, pp. 462-469.
Author Response
Dear reviewer:
On behalf of my co-authors, we are very grateful to you for giving us the opportunity to revise our manuscript. We appreciate your positive attitude and constructive comments and suggestions on our manuscript entitled " Considering the Effect of Non-Propagating Cracks on Fatigue Limit Prediction in the Critical Distance Method Framework " ( ID: applsci-1981522).
We have carefully studied your opinions and tried our best to revise our manuscript according to the comments. The following are the responses and revision. I have answered your questions and suggestions on an item-by-item basis. We also attach the revised manuscript.
Comment 1: Page 3, line 3b, 2b - is Fi. 4 and Mpa a should be Fig. 4 and MPa.
Response: We carefully revised the format of the unit.
Comment 2: In Fig. 3 you can see some sample devices mounted, it would be good to describe them in the text.
Response: We resubmit Fig. 3 and introduce each part of the fatigue test system one by one in Fig. 3.
Comment 3: Fig. 4 - no scale in the drawing.
Response: We resubmit Fig. 4 and give the scale in Fig.4
Comment 4: The question is what is the fracture length in Fig. 4b? There is propagation, it can be seen, only in terms of short or long cracks?
Response: The crack in Fig. 4b is non-propagating crack, and it does not continue to expand after 37524 cycles. Therefore, the specimens did not fracture at 106 cycles. The length of non-propagating crack is 0.425mm. Non propagating crack usually mean that the short crack, affected by the crack closure effect, will stop growing after propagating a certain length under fatigue limited.
Comment 5: In the caption Fig. 4 there is no caption for a) and b).
Response: We add the title of Fig. 4 (a) and (b)
Comment 6: On Figs. 5, 8, 10, 11 and parts in the whole work we have Mpa, and it should be MPa.
Response: We have carefully revised the format of the unit in the picture and text of the whole article.
Comment 7: Very little information on FE modeling itself.
Response: We have revised information of FE modeling and hope that it is now clearer. Please see page 8 of the revised manuscript, lines 5-9.
Comment 8: It would be worthwhile to quote in the introduction also papers of: 1) J. Lewandowski, D. Rozumek, Fatigue crack growth in welded S355 samples subjected to bending loading. Metals, Vol. 11, 1394, 2021, 2) D. Rozumek, Z. Marciniak, Fatigue properties of notched specimens made of FeP04 steel. Materials Science, Vol. 47, No. 4, 2012, pp. 462-469.
Response: In the introduction section, we quote the recommended article. The label of literature are [4] and [5].
We would like to thank you again for taking the time to review our manuscript.
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
The Authors took into account all comments of the Reviewer. After considering the comments, the work is more understandable to the reader. Based on the above mentioned, I recommend publishing the article in the journal Applied Sciences.
