Hi Adisa,

You have made an error in geometry construction.

If the inner radius is 1 mm and the thickness is 2 mm, then the outer radius must be 3 mm. You used 2 mm.

You were also missing the 4 and 6 mm dimensions.

You quote only one calculated stress, but there are two Sigma Y values, one on the left and one on the right,
because the bending moment is +/- c but the Fy/A is only a compressive stress.