Understanding the crystallography of the eutectoid microstructure in a Zn-Al alloy using the edge-to-edge matching model

The orientation relationship (OR) between the β(Zn) phase and the α(Al) phase and the corresponding habit planes in a Zn-Al eutectoid alloy were accurately determined using convergent beam Kikuchi line diffraction patterns. In addition to the previously reported OR: [112-bar 0]β-bar [110]α (0002)β-bar (1-bar 11)α, two new ORs were observed. They are: [112-bar 0]β-bar [110]α (1-bar 101)β 0.82o from (002)α and [1-bar 100]β-bar [112]α (0002)β 4.5o from (1-bar 11)α. These ORs can be explained and understood using the recently developed edge-to-edge matching model