Answer
Groove deformation occurs when the compressive stress exerted by the retaining ring exceeds the yield strength of the groove material (often aluminum or soft steel). The maximum thrust capacity based on groove yield is $P_g = \frac{D \cdot d \cdot \pi \cdot \sigma_y}{K}$, where $D$ is the diameter, $d$ is the groove depth, $\sigma_y$ is the yield strength of the groove material, and $K$ is a safety factor (usually 2). If $P_{applied} > P_g$, the groove wall will deform plastically, creating a 'ramped' profile. This ramping causes the retaining ring to dish (tilt), which introduces a radial component of force that can eventually eject the ring from the groove. To prevent this, engineers should specify hardened grooves or increase the groove depth, provided the shaft's structural integrity remains within limits.
