Tool Damage Form |
Causes |
Countermeasure |
Flank Wear |
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- Tool grade is too soft.
- Cutting speed is too high.
- Flank angle is too small.
- Feed rate is extremely low.
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- Tool grade with high wear resistance.
- Lower cutting speed.
- Increase flank angle.
- Increase feed rate.
|
Crater Wear |
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- Tool grade is too soft.
- Cutting speed is too high.
- Feed rate is too high.
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- Tool grade with high wear resistance.
- Lower cutting speed.
- Lower feed rate.
|
Chipping |
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- Tool grade is too hard.
- Feed rate is too high.
- Lack of cutting edge strength.
- Lack of shank or holder rigidity.
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- Tool grade with high toughness.
- Lower feed rate.
- Increase honing. (Round honing is to be changed to chamfer honing.)
- Use large shank size.
|
Fracture |
|
- Tool grade is too hard.
- Feed rate is too high.
- Lack of cutting edge strength.
- Lack of shank or holder rigidity.
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- Tool grade with high toughness.
- Lower feed rate.
- Increase honing. (Round honing is to be changed to chamfer honing.)
- Use large shank size.
|
Plastic
Deformation |
|
- Tool grade is too soft.
- Cutting speed is too high.
- Depth of cut and feed rate are too large.
- Cutting temperature is high.
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- Tool grade with high wear resistance.
- Lower cutting speed.
- Decrease depth of cut and feed rate.
- Tool grade with high thermal conductivity.
|
Welding
|
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- Cutting speed is low.
- Poor sharpness.
- Unsuitable grade.
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- Increase cutting speed. (For DIN Ck45, cutting speed 80m/min.)
- Increase rake angle.
- Tool grade with low affinity. (Coated grade, cermet grade)
|
Thermal Cracks |
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- Expansion or shrinkage due to cutting heat.
- Tool grade is too hard.
*Especially in milling.
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- Dry cutting. (For wet cutting, flood workpiece with cutting fluid)
- Tool grade with high toughness.
|
Notching |
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- Hard surfaces such as uncut surfaces, chilled parts and machining hardened layers.
- Friction caused by jagged shape chips. (Caused by small vibration)
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- Tool grade with high wear resistance.
- Increase rake angle to improve sharpness.
|
Flaking |
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- Cutting edge welding and adhesion.
- Poor chip disposal.
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- • Increase rake angle to improve sharpness.
- Enlarge chip pocket.
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Flank Wear Fracture
*Damage for
polycrystallines |
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- Damage due to the lack of strength of a curved cutting edge.
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- Increase honing.
- Tool grade with high toughness.
|
Crater Wear Fracture
*Damage for
polycrystallines |
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- Tool grade is too soft.
- Cutting resistance is too high and causes high cutting heat.
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- Decrease honing.
- Tool grade with high wear resistance.
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