 Solution

The lamellar interfaces now make $60^{\circ }$ with the surface normal, or $30^{\circ }$ with the surface itself. Draw inclined alternating plates rather than vertical stripes, with preferentially etched ferrite below the more resistant cementite.

The upper panel shows an inclined microstructure intersecting the original plane. Differential etching can expose a shallow inclined cementite face on one side of a ridge and an undercut or overhang on the other. The lower panel shows its accessible height profile, with additional rounding from a finite tip. It is therefore possible to obtain an asymmetric ridge even from an initially planar section through parallel lamellae.

For an ideal unetched planar cut, a plate of normal thickness $d$ has apparent surface widthThe same factor applies to the ferrite spacing. Inclination alone broadens all intersections together; it does not by itself change the true phase-width ratio.