· KAIPU Engineering · glossary · 1 min read
undefined — Industry Glossary Entry
Definition of thermal fatigue in industrial cutting: failure by repeated thermal cycling at the edge, common on high-speed tissue and film slitting without active cooling.
undefined is a specific failure mode where repeated heating and cooling of the cutting edge grows micro-cracks that eventually chip the edge. Thermal fatigue is the dominant failure mode on high-speed tissue and film slitting without active cooling.
Visual tells
- A “network” of micro-cracks visible under 10× magnification, parallel to the edge
- The first chip is usually at the high-wear point of the edge (often the centre)
- Edge temperature can be inferred from the colour: straw (200–250 °C) → blue (300 °C) → purple (400 °C)
Fixes
- Apply a hot-hardness coating (TiAlN, AlCrN, CrAlN)
- Switch to a hot-hardness steel (M2 with TiAlN, M35, M42)
- Add active cooling (air or water-mist) aimed at the cut zone
- Verify the hone is ≥ 10 µm on a high-speed line
See also: Fatigue wear, Chipping, Maintenance: how to extend slitter life.