Official Answer
Answer
Shear failure occurs when the thrust load exceeds the material's shear strength, effectively 'cleaving' the ring along the line of the groove edge. This is a brittle failure mode and is more common in rings with very high hardness (HRC > 52). While higher hardness increases the shear strength $S_s$, it reduces the material's fracture toughness. If the ring is subjected to impact loads, a high-hardness ring may snap rather than deform. For most applications, a hardness range of HRC 44-48 for carbon steel or HRC 40-45 for 17-7PH provides the optimal balance between shear strength and impact resistance.
