In a roller kiln operating at high temperature,
SiC rollers showed edge chipping at the roller ends after a period of operation.

The damage was localized and repetitive, raising concerns about material failure.

The issue was initially attributed to:

• Insufficient material strength
• Brittleness of ceramic material
• Possible overload

Inspection showed:

• Damage concentrated at roller end edges
• No fracture through the full cross-section
• Progressive chipping rather than sudden breakage

This indicates a localized phenomenon, not bulk failure

The system behavior can be summarized as:

• Load is transferred through roller ends
• Contact occurs at limited regions
• Roller behaves as a beam under load

Result:

• Bending dominates
• Edge experiences higher stress concentration

The failure develops through:

• Localized contact at support interface
• Repeated loading cycles
• Stress concentration at edge
• Progressive material removal

Edge chipping is:

A contact-induced damage mechanism under bending-dominated loading

Not caused by insufficient material strength.

Design focus should be on:

• Contact condition optimization
• Load distribution
• Support structure design

Not only material properties.