High Performance Machining of Titanium The Systems Approach · Tunable Milling Adapter Beyond...
Transcript of High Performance Machining of Titanium The Systems Approach · Tunable Milling Adapter Beyond...
October 5th, 2011
T.J. Long, Ruy Frota, and Steve Chen
Kennametal Technology Center
Latrobe, PA
High Performance Machining of Titanium
The Systems Approach
Agenda
• Challenges in machining Titanium
• Thermal Management
• Importance of Spindle Connections
• Maximizing Dynamic Stiffness
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KM4XTM
Tunable Milling
Adapter
Beyond BlastTM
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Challenges in Machining Titanium
90% of work from metal
cutting is converted into
heat
X (mm)
Y(m
m)
4.8 4.9 5 5.1 5.2 5.3
1.8
2
Temperature (C)
1000
950
900
850
800
750
700
650
600
550
500
450
400
350
300
250
200
150
100
Third Wave AdvantEdgeThird Wave AdvantEdge • Good high temperature strength
increases the work needed to cut
Titanium.
• High work hardening and strain rate
sensitivity exacerbate thermal issues
in cutting Ti alloys.
• Titanium reacts with most materials
at high temperatures to chemically
wear tools.
• Poor thermal conductivity of Ti
causes heat to partition to the tool
instead of the chip.
Titanium Characteristics
Time (s)
Fo
rce
-X(N
),F
orc
e-Y
(N)
Te
mp
era
ture
(C)
0 0.001 0.002 0.0030
100
200
300
400
500
600
700
0
200
400
600
800
1000Force-X (N)
Force-Y (N)
Temperature (C)
Time (s)
Fo
rce
-X(N
),F
orc
e-Y
(N)
Te
mp
era
ture
(C)
0 0.0005 0.001 0.00150
200
400
600
800
1000
0
200
400
600
800
1000Force-X (N)
Force-Y (N)
Temperature (C)
50 m/min at 0.15 mm chip 100 m/min at 0.15 mm chip
Effect of Cutting Speed on Temperature
Increase Tool Temp +250oC
Current Ti cutting conditions Double Cutting Speed
FEM predicts a 250°C increase in cutting temperature to
double speed
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0.00
0.50
1.00
1.50
2.00
2.50
Rela
tive T
oo
l L
ife
Std Coolant Beyond Blast
T124755 KSSM 45° Lead Angle
Beyond Blast vs. Standard Through Coolant
KSSM45 Milling Tool Development
KSSM45 Beyond BlastTM provided over 2 times better tool life than
standard through spindle coolant delivery.
Cutting Conditions
Workpiece: Ti6Al4v
Hardness: 42 – 46 HRC
Length of Pass: 254mm (10 in)
Cutting Fluid: Water based Synth.
Coolant Pressure: 300 psi.
Cutting Parameters
Cutting Speed: 58 m/min (187 SFM)
Chip load (fz): 0.25mm/tooth(0.010 ipt)
Axial Depth of Cut = 2 mm (0.08 inch)
Radial Depth of Cut = 81 mm (3.2 inch)
Baseline
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0.00
0.50
1.00
1.50
2.00
2.50
3.00
Re
lati
ve
To
ol L
ife
Std Coolant
150 SFM
Beyond Blast
150 SFM
Std Coolant
187 SFM
Beyond Blast
187 SFM
T114526 & T117470 Daisy Round Inserts
Beyond Blast vs. Standard Through Spindle Coolant
Std Coolant
Beyond Blast
Daisy Milling Tool Development
DAISY Beyond BlastTM provided over 2.5 times better tool life than
standard through spindle coolant delivery @ 150 SFM.
Cutting Parameters
Cutting Speed: 46 m/min (150 SFM)
& 58 m/min (187 SFM)
Chip load (fz): 0.25mm/tooth(0.010 ipt)
Axial Depth of Cut = 3.8 mm (0.15 inch)
Radial Depth of Cut = 51 mm (2.0 inch)
Cutting Conditions
Workpiece: Ti6Al4v
Hardness: 42 – 46 HRC
Length of Pass: 254mm (10 in)
Cutting Fluid: Water based Synth.
Coolant Pressure: 1000 psi.
Baseline
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Turning Facing Profiling Square Shank
R S
tyle
Op
era
tio
ns
Coolant Path Shim position determines coolant path
• Shim side 1 up
• Rotate shim 90°
for facing
• Shim side 2 up (flip
shim over)
• Broader coolant
dispersal for profiling
• Shim side 1 up
• Position coolant
slot toward end for
turning
Technical details – R Shape Geometries
Cutting Parameters
Cutting Speed: 91 m/min (300 SFM)
Feed: 0.2 mm/rev (0.008 ipr)
Depth of Cur: 1.27 mm (0.05 inch)
Cutting Conditions
Workpiece: Ti6Al4v
Hardness: 42 – 46 HRC
Cutting Fluid: Water based Synth.
Coolant Pressure: 100 and 1000 psi.
Cutting Conditions
Workpiece: Ti6Al4v
Hardness: 42 – 46 HRC
Cutting Fluid: Water based Synth.
Coolant Pressure: 100 and 1000 psi.
Cutting Parameters
Cutting Speed: 30 and 45.5 m/min (100 and 150 SFM)
Feed: 0.305 mm/rev (0.012 ipr)
Depth of Cur: 6.35 mm (0.25 inch)
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Turning Tool Development
Agenda
• Challenges in machining Titanium
• Thermal Management
• Importance of Spindle Connections
• Maximizing Dynamic Stiffness
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KM4XTM
Spindle Connections - Overview
Where we are today…
ASME B5.50
DIN 69871
ISO 7388
JIS B6339
ISO26622
(KM System)
DIN 69893
ISO12164
(HSK)
ISO26623
(PSC System) ISO 7388
With Face contact
Kennametal’s Next Spindle
Generation of KM™
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KM4X Next Generation Spindle Connection
Kennametal’s Next Spindle
Generation of KM™
• Highest rigidity and bending capacity
among all connections
• Evenly distributed clamping force
• Simple design allows for front-loaded
spindle configurations
• Balanced by design for high spindle
speed capability
• Capable of performing in a wide range of
operations from low speed, high torque to
high speed, low torque.
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Load-Deflection Charts KM4X63 versus PSC63
KM4X63 shows higher stiffness and separation bending moment than PSC63 at same clamping force
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Load-Deflection Charts KM4X63 versus HSK63
KM4X63 shows 4X higher stiffness at 600 Nm and 8X at 900 Nm
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1.00 1.00
0.86
0.270.21
0.080.06
0.82
0.440.36
0.140.19
0.060.06
0.37
0.160.14 0.09
0.17
0.05 0.05
0.00
0.20
0.40
0.60
0.80
1.00
1.20
No
rmalized
Sti
ffn
ess
1800 3000 6000
Bending Moment [N.m]
KM4X125
KM4X100
HSK125A
HSK100A
CV60
BCV50
CV50
Load-Deflection chart
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0 1000 2000 3000 4000 5000 6000
Bending Moment [Nm]
Defl
ecti
on
[m
m]
@150m
m
BCV50
CV50
HSK100A
KM4X100
Load-Deflection chart
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
0.20
0 1000 2000 3000 4000 5000 6000
Bending Moment [Nm]
Defl
ecti
on
[m
m]
@150m
m
CV60
HSK125A
KM4X125
Load-Deflection Charts KM-HSK-Steep Taper
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Cutter Diameter: 80 mm
Number of flutes: 4
Projection Length: 250 mm
Cutting Speed: 50 m/min
ADOC: 63.5 mm
RDOC: 12.7 mm
Feed Rate: 142 mm/min
MRR: 361 cm3/min
Torque: 870 Nm
Bending Moment: 4620 Nm
MRR is limited by maximum the bending moment of spindle interface
0
500
1000
1500
2000
2500
3000
3500
4000
0 500 1000 1500 2000
Spindle Speed [rpm]
To
rqu
e [
Nm
]
Spindle Torque Curve Operating Point Torque Limited by Bending
Application Data – Ti Milling on HSK125A machine
Cutter Diameter: 300 mm
Number of Inserts: 20
Projection Length: 150 mm
Cutting Speed: 46 m/min
ADOC: 9.5 mm
RDOC: 150 mm
Feed Rate: 195 mm/min
MRR: 284 cm3/min
Torque: 2905 Nm
Bending Moment: 2860 Nm 0
500
1000
1500
2000
2500
3000
3500
4000
0 500 1000 1500 2000
Spindle Speed [rpm]
To
rqu
e [
Nm
]
Spindle Torque Curve Operating Point Torque Limited by Bending
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Agenda
• Challenges in machining Titanium
• Thermal Management
• Importance of Spindle Connections
• Maximizing Dynamic Stiffness
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Tunable Milling
Adapter
Tunable Adapters provide significantly higher dynamic stiffness
Tunable Milling Adapters
Acceleration vs. Dynamic Stiffness
0.06
0.07
0.08
0.09
0.1
0.11
0.12
5.00E+06 7.00E+06 9.00E+06 1.10E+07 1.30E+07 1.50E+07
Dynamic Stiffness (N/m)
Accele
rati
on
(m
/s2)
Normalized Dynamic Stiffness
0.00
0.20
0.40
0.60
0.80
1.00
1.20
0 1 2 3 4 5 6 7 8 9Number of turns
SK50 L=300mm
SK50 L=260mm
• Optimal Dynamic Stiffness. Adapter can be tuned on the spindle to account for machine dynamics
• Improved surface quality and close tolerances
• Increased productivity. Larger depth of cut and feed rate.
• Significant reduction on vibration for extended tool life, longer spindle bearing life
0.76
0.25
1.00
0.32
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
Dyn
am
ic S
tiff
ness (
No
rmali
zed
)
Machine A Machine B
Dynamic Stiffness of Damped Milling Adaptors
Tunable Standard Toolholder
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It’s Not Just About the Tools:
It Is About Partnerships, Digitization and Integration
Design Part
with CAD
Select
Machine Select Tools
Write & Optimize
Program Produce Part Inspection
That Can be Optimized
A Complex Iterative Process
0 10 20 30 40 50 60 70 80 90 100
Optimized
Baseline
Forging/Casting Machine Tool Cutting Tools Machining Other
The Opportunity
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