Flank wear

Preferable wear type in every applicationOffers predictable and stable tool life. Cutting speed too high Too tough grade Insufficient wear resistance Lack of coolant. Reduce cutting speed Select a more suitable grade depending on demand on toughness or wear resistance Add coolant.

Notch wear Sticky and/or work-hardening materials Use of ~90 entering angle Geometry is too negative Select a sharper edge Decrease entering angle Select a CVD-coated grade, e.g. 4325 (for increased wear resistance) Select a PVD-coated grade, e.g. 1125 (for flaking and built-up edge resistance) Vary depth of cut.

Crater wear

Too high cutting speed and/or feed Too tough grade Chip breaker too narrow Reduce cutting speed or feed Select a more wear resistant grade Select a more open/positive geometry.

Plastic deformation, depression/impression

Depression

Impression High heat load and pressure, cutting temperature too high Grade too tough/soft Lack of coolant supply Reduce heat and pressure load by reducing cutting speed and/or feed If edge depression, reduce feed first If flank depression, reduce speed first Select a more wear/heat resistant grade Select a more open/positive geometry Improve coolant supply.

Built-up edge (B.U.E)

Too low cutting temperature Welding of the chip on insert Sticky/smeary material Geometry too negative Increase cutting temperature by increasing speed or feed Select a PVD-coated grade, e.g. 1125 (less BUE on PVD-coatings) Select a more positive geometry.

Chipping outside cutting zone

Chip jamming because of facing towards shoulder The chips are deflected against the cutting edge Not optimized feed or feed direction Change operation path (to avoid facing towards shoulder) Change feed Change to a PVD-grade, e.g. 1125 Select an insert geometry that alters the chip flow.

Chipping on edge

Unstable conditions Grade too hard/brittle Make the machine conditions more stable Select a tougher grade Select a stronger geometry

Thermal cracks

Varying cutting edge temperatures Intermittent cuts and coolant Grade is sensitive to heat shock variations Switch off coolant or apply coolant copiously to obtain an even temperature level Decrease cutting speed

Breakage Excessive wear Grade too tough (deformation and-breakage) Grade too hard Run shorter (time in cut) operations: check how wear begins and the dominant wear type Change cutting data Select a more suitable insert/geometry

Slice fracture - ceramics Excessive tool pressure. Reduce the feed. Select a tougher grade. Select an insert with a smallerchamfer, or use another geometry to change cutting force direction.