Техническая информация Sumitomo - страница 3

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Tool Failures and Tool Life

  • Forms of Tool Failures
Cat.No.Name of FailureCause of Failure
from Causes(1) to (5)Flank WearDue to the scratching effect of hard grains contained in the work material.
Resulting Mechanical(6) (7)Chipping FractureFine breakages caused by high cutting loads or chattering. Large breakage caused by the impact of excessive mechanical forces actingon the cuttingedge.
from eactions(8)Crater WearSwaft chips removing tool material as it flow over the top face at high temperatures.
Resulting Chemical R(9) (10) (11)Plastic Deformation Thermal Crack Built-upEdgeCutting edge is depressed due to softening at high temperatures. Fatigue from rapid, repeated heating and cooling cycles during machining. Adhesion or accumulation of extremely-hard work material on the cuttingedge.
  • Tool Wear Forms of Tool Wear

Flank Wear Crater Wear

Bad chip control cutting edge fracture Burrs occur Initial wear Crater wear K Sudden T increase

Poor surface finish Side flank wear in wear

Crater Wear VN1 Steady wear Face flank wear VN2

Cutting Time T (min) Cutting Time T (min) Flank average wear VB

Flank Wear・ Wear increases rapidly right after cutting・ Wear increases in proportion to the
Edge wear VC
Higher cutting forcestarts, it then progresses at a moderate andcutting time.

Poor machining accuracy, proportionate pace up to a certain point Burrs occur where it suddenly increases rapidly again.

  • Tool Life (V-T)

・ This double logarithm graph shows the relative tool life of the specified wear over a range of cutting speeds on the X-axis, and the cutting speed along the Y-axis.

Flank Wear Crater Wear

vc1 vc2vc3v 1v 2v 3v 4
cccc
vc4
VKT
B
T TTTT'T'T'T'
1234
1 234
Cutting Time (min)Cutting Time (min)
InInv
v 1c1

In c In v v 2 c2 In c Inv v 3 c3 In c Inv v 4 c4 c

InT1 InT2 InT3 InT4 InT'1 InT'2 InT'3 InT'4

Tool Life (min) Tool Life (min) N