Tool Wear
|
Remedy |
| Flank wear 
|
General criterion for end of tool
life, characterized by an admissible amount of flank wear. |
- Select more wear-resistant grade
- reduce cutting speed
|
| Notch wear 
|
Occur locally in the area of the primary
cutting edge where it contacts the work-piece surface. Caused by hard surface layers and
work-hardened burrs, especially on stainless austenitic steels. Danger of breakage! |
- strengthen cutting edge
- select smaller approach angle(450)
- reduce feed
|
| Crater wear 
|
Wear on the rake face, primarily
characterized by crater depth. |
- use coated hardmetal grades
- select positive insert geometries
- reduce cutting speed reduce chip cross-section
|
| Edge chipping 
|
Minor chipping along the cutting edge,
usually accompanied by flank wear and therefore not always identifiable. Danger of
breakage! Edge chipping outside the cutting area is the result of chip impact due to
unfavorable chip removal |
- select tougher grade
- use insert with stronger cutting edge geometry
- reduce feed when starting the cut in the case of damage due to chip impact.
- vary feed
- change chipbreaker geometry
- change approach angle
|
| Insert breakage 
|
Insert breakage usually means damage to
tool and workpiece. Causes are varied and also depend on machine and workpiece. Often
originates in notches or excessive wear. |
- select tougher grade
- use stronger insert with larger corner radius
- select chipbreaker geometry for heavier chip sections
- reduce feed and possibly also depth of cut
|
| Built-up edges 
|
Edge built-up occurs on the rake face as a
result of work material welding together with the cutting material, especially when
cutting difficult to machine materials. From time to time the built up edge
will break off and make cause damage to the cutting edge. Built-up edges result in
poor surface finishes. |
- increase cutting speed
- use coated hardmetals or cermets
- select positive cutting edge geometry
- use cutting fluid
|
Plastic deformation
 |
Caused by overloading of the cutting edge combined with
high machining temperatures. Danger of breakage! |
- reduce cutting speed
- lower feed
- use more wear resistant hardmetal grade
|
