1. Apparently, figure 3-a shows dimples significantly larger than those shown in the cross-section (figure 3-b). In fact, it is difficult to understand what figure 3-b, labeled as its cross-sectional microstructure, represents. Apparently, what you see is the geometry of the dimples filled with another material and not microstructural aspects. Besides, an explanation and justification for the complex geometry of the dimple is necessary. On the other hand, indicating the location of the wear tracks shown in figures 8-a and 8-b in figure 3-a would be quite didactic and enlightening.
2. Why did the authors use Si3N4 balls as a counter-body? What is their surface topography?, Besides, it seems that in the phrase “Si3N4 ball (6mm) is used for the grinding ball” the word “griding” is not adequate.
3. Figure 4: the use of a single scale would greatly facilitate the comparison.
4. In the analysis of figure 4, the authors state that: "In Fig. 4b, the variation law of the friction coefficient curve is similar to that of the ESPL, indicating that friction coefficient and friction noise have some connection". Unfortunately, I'm afraid I have to disagree with this statement. The time required for the steady-state of the two variables to be achieved is very different (about 1200 s for the sound pressure and less than 400 s for the friction coefficient. This point needs to be better evaluated, explained, and discussed. Besides, the evolution of the friction coefficient with time for the MA samples has two extremely relevant fluctuations before reaching the steady-state. This point needs to be indicated in the manuscript and needs to be further explained. Blau (Blau PJ. On the nature of running-in. Tribol Int 2005; 38: 1007–12. Also Blau PJ. Friction science and technology. 2nd ed.CRCPress; 2009) with consequent incorporation into the discussions, and obviously in the text of the manuscript.
5. In figure 7a: sliding direction instead of sliding debris.
6. The speculations about the wear resistance based on figure 8 are very difficult to be accepted. Besides not having statistical representativeness (the dispersion of the data [34-63 µm and 46-59 µm] was not reported, it was not clear how they were measured. Also, it does not seem right to call abrasive wear without an adequate characterization of the mechanisms acting on the two sample classes. Figure 7 shows very different degradation mechanisms.

I thank the authors for a much clearer version and the interesting discussion/response to my remarks. I believe that after the modifications made by the authors the paper has reached an acceptable level of quality and can be published in Industrial Lubrication and Tribology.

As already indicated in Revision #1, the authors performed a good analysis of all reviewer’s considerations, and the paper is now ready for publication in Industrial Lubrication and Tribology.

After multiple reviews, the paper has reached a satisfactory quality level and can be published in Industrial Lubrication and Tribology.