Wear Behavior of the Multiheterostructured AZ91 Mg Alloy Prepared by ECAP and Aging

Figure 7

The fluctuation of the COF values of the AC (a, c) and MH (b, d) alloys under the applied load of 4.9 N (a, b) and 14.7 N (c, d).

(a)

(b)

(c)

(d)