Tooling's wear and damage
◆Wear of toolings and countermeasures
Tooling damage form
Caused
Countermeasure
Wear of major flank
●
 Tooling material is too soft
●
 Cutting speed is too high
●
 Back rake angle is too small
●
 Feeding is too little
●
 Select high wear resistant tooling materialst
●
 Reduce cutting speedh
●
 Increase back rake angle
●
 Increase feeding
Wear of front surface(crescent hole wear)
●
 Tooling material is too soft
●
 Cutting speed is too high
●
 Feeding is too much
●
 Select high wear resistant tooling materialst
●
 Reduce cutting speedh
●
 Decrease feeding
Damage (little chipping)
●
 Tooling material is too hard
●
 Feeding is much
●
 Strength of cutting edge is not enough
●
 Rigidity of tooling rod, tooling holder is not enough
●
 Select tooling material with good toughnesst
●
 Decrease feeding
●
 Increase edge regrinding volume
 (if it is rounding, change it to chamfer)
●
 进给量太小 Feeding is too little
Damage
●
 Tooling material is too hard
●
 Feeding is much
●
 Strength of cutting edge is not enough
●
 Rigidity of tooling rod, tooling holder is not enough
●
 Select tooling material with good toughnesst
●
 Decrease feeding
●
 Increase edge regrinding volume
 (if it is rounding, change it to chamfer)
●
 Feeding is too little
plastic deformation(blade sinks)
●
 Tooling material is too soft
●
 Cutting speed is too high
●
 Cutting depth, feeding is too much
●
 Temperature of cutting edge is too high
●
Select tooling material with good toughnesst
●
 Reduce cutting speed
●
 Reduce cutting depth, feeding
●
 Select tooling materials with high
coefficient of heat conductivitye
Accumulated lump of chips (number of melting)
●
 Cutting speed is low
●
 Cutting edge is not sharp
●
 Tooling material is not appropriate
●
 Increase cutting speed (S45C: more than 80m/min) t
●
 Enlarge rake angle
●
 Select tooling materials with small affinity
(coating, ceramet)
Thermal cracking
●

Expansion and shrinkage caused by cutting heatt
●
 Tooling material is too hard
※Especially when milling
●
 Dry cutting
 (for wet cutting, must have sufficient cooling fluid)
●
Select tooling materials with good toughness
Boundary wear
●
 Oxide chill layer and machining hardened layer
lead to hardening of work piece surface
●


Indented cutting cause wear
(produced by little vibration)
●
 Select high wear resistant tooling materials
●
 Enlarge rake angle to make cutting edge sharp
Peeling
●
 Number of melting on cutting edge
●
 Unsmooth discharge of cut chips
●
 Enlarge rake angle to make cutting edge sharp
●
 Enlarge blade's chip flute
Wear, damage of major flank
※ This damage happens with ultra high pressure sintered body
●
 Typical damage caused by insufficient strength
of cutting edge
●
 Increase edge regrinding volume
●
 Select materials with good damage resistance
Wear, damage of front surface (crescent hole wear)
※ This damage happens with ultra high pressure sintered body
●
 Tooling material is too soft
●
 Cutting resistance is large, cutting temperature
is highh
●
 Select materials with good wear resistance
●
 Decrease edge regrinding volume