Quality Diagnostics · D06
Discoloration after gamma sterilization is normal and doesn't affect mechanical performance - color recovers after a 300°C treatment.
Gamma-Sterilization Discoloration
Measured Data
Zirconia, 50kGy sterilization. Result: density 6.05g/cm³ (unchanged before/after), strength 320N (was 325N before), a 1.5% difference. Alumina: slight yellowing, density and strength unchanged, reversible at 300°C.Mechanism: gamma rays trigger a reversible chemical reaction at ceramic grain boundaries, causing the color shift - a physical/chemical material property, not a quality defect. Held at 300°C, color returns to its original state.
Note: cosmetic parts should confirm acceptable color-shift tolerance during product validation. Performance-critical parts: discoloration doesn't affect mechanical performance and can be used with confidence.