Fig. 1 SEM surface micrographs of the samples before the wear tests: ( a ) AZ91 bare alloy, ( b ) S sample, and ( c ) A + P sample More

Fig. 2 XRD patterns of the bare alloy (AZ91 Mg alloy) and the MAO coatings (S and A + P samples) (Reproduced with permission from Ref. [ 30 ]. © 2021 Springer Nature.) More

Fig. 3 Loading–unloading curves of the samples during the indentation test More

Fig. 4 Stereo microscope images of the surfaces after the wear tests: ( a ) AZ91 bare sample (RT), ( b ) AZ91 bare sample (200 °C), ( c ) S sample (RT), ( d ) S sample (200 °C), ( e ) A + P sample (RT), and ( f ) A + P sample (200 °C) More

Fig. 5 Wear track profiles of the samples: ( a ) RT and ( b ) 200 °C. The insets show the profiles of the S and A + P samples. More

Fig. 6 Wear-rates of the samples coated in different electrolytes at RT and 200 °C More

Fig. 7 Variation of the wear-rate with the ratio of H 3 / E 2 More

Fig. 8 Variation of COF of the samples with sliding distance: ( a ) RT and ( b ) 200 °C More

Fig. 9 SEM images of the wear tracks: (( a ) and ( b )) bare AZ91 alloy, (( c ) and ( d )) S sample, (( e ) and ( f )) A + P sample. ( a ), ( c ), and ( e ) for RT; ( b ), ( d ), and ( f ) for 200 °C. More

Fig. 10 EDS mapping analysis for oxygen within the wear track of AZ91 bare alloy tested at 200 °C More

Fig. 11 Variation of COF of the S sample with sliding distance at various normal load and sliding speed More

Fig. 1 Sketch of the structure of a mono-sheet type film More

Fig. 2 Schematic representation of the FE model More

Fig. 3 Example of a pressure–overclosure curve More

Fig. 4 Sketch for calculating the interface law More

Fig. 5 Resulting contact areas in mm 2 of the pressure measurement film MS for contact situations of Table 1 More

Fig. 6 Resulting contact area in mm 2 of the pressure measurement film HS for contact situations of Table 1 More

Fig. 7 Resulting contact area in mm 2 of the pressure measurement film HHS for contact situations of Table 1 More