Figure 3
From: Effect of solution treatment on the fatigue behavior of an as-forged Mg-Zn-Y-Zr alloy

Optical microscopy observation to the as-forged and T4 treated samples subjected to fatigue testing at stress amplitudes of 100 MPa and 70 MPa respectively for: (a,b) 0, (c,d) 103, (e,f) 105 and (g,h) 5 × 106 cycles. Images of (a,c,e,g) were taken on an as-forged sample surface; Images (b,d,f,h) were taken on a T4 treated sample surface.