Relationship between characteristics HO / T and S / ho of disc spring

In general, we expect the spring force to increase with the increase of disc spring deformation, but the spring force / deformation curve of most disc springs is nonlinear, and the curve curvature increases with the increase of HO / T.
When the HO / T is less than 1.5, the disc spring can keep the flattening state stably. When the HO / T is greater than 1.5, the disc spring will reverse. When HO / T is greater than 2, the disc spring will reverse when it is close to the pressure level.