Page 192 - Tungaloy Catalog

T-CBN (PCBN) Series

T-CBN series for machining hardened steels and hard materials

j Application area Necessity of PCBN grades d Features of CBN grades for machining
The condition material is: hardened steel and other hard materials
necessary to cut Hardness of tool ≥ Hardness of tool X 3 Impact resistance 980 400
the work
65
d Hardened steel (60HRC) → 700 Hv d Cemented carbide → 1600 Hv
3 Workpiece hardness (HRC) 60 Ceramic T-CBN d Effects of grain size of CBN on surface roughness and cutting speed Increasing Wear resistance 500 330
d PCBN (BX360) → 3300 Hv
[Rough-grained CBN]
[Fine-grained CBN]
55
165
50
PCD and PCBN Tools Basic selection of T-CBN grades in machining of hardened steel and hard material 100 0 55 60 65 0 300
Coated / Cermet
45
CBN content
1-2μm
4-8μm
Heavy
Continuous
Light
Less CBN content e Increasing wear resistance
Rough grained PCBN. CBN particles
Fine grained PCBN provided with
interrupted
interrupted
hold firmly.
sharp cutting edge.
More CBN content e Increasing impact resistance
Cutting mode
Good surface roughness
Allows high speed machining
d Uncoated T-CBN grades
d Coated T-CBN grades
BX310 For high speed / Priority on wear resistance in
BXM10 For high speed cutting continuous cutting
BX330 For medium speed / Priority on surface quality
BXM20 For general purpose
BX360 For low to medium speed / General purpose
grade, excels in impact resistance
BXC50 For Interrupted cuts BX380 For low to medium speed / Priority on impact
resistance in heavily interrupted cutting 600
300
j Application area of coated T-CBN grades 250
d Continuous cutting d Interrupted cutting 200 400
150 200
980
980
Cutting speed Vc (SFM) 660 BXM20 cutting Cutting speed Vc (SFM) 660 BXM20 interrupted 0 0
100
BXM10
BXM10
50
Lightly
Continuous
330
330
0 Interrupted
0 .006 .012 Light Interrupted Heavy
Feed: f (in/rev)
BXM10 For high speed BXM20 For general purpose
Longer life at high speed First choice
BXM10 For high speeds 5000
Applicable for high speeds 5000
exceeding Effects of Coated T-CBN grades 3300
v c = 200 SFM 3300
d Protect CBN from oxidation wear
Coated on hard CBN Since the coating layer intercepts air, oxidation wear of Improved resistance 1650
CBN can be prevented.
Hardness: d Peeling of coating layer can be protected to flank wear 1650
CBN > Coating layer Hard and deformation resistant CBN is excellent substrate
material. 0
Effects of coolant in machining of hardened steel .040 .080 .120 .160
d Continuous cutting dInterrupted cutting
19 d In continuous cutting, wet 2000
Cutting conditions Heavy cutting is superior to dry 1600
.004
Flank wear width VB (in) .003 Cutting conditions cutting Tool life (min) 10 5 10 d Cutting speed: Vc = 330 SFM cutting in tool life for wear. .012 1200
d Work material: Chromium
15
molybdenum steel
Dry
Wet
Continuous
14
interrupted
(JIS SCM415), 60 HRC
d In interrupted cutting, dry
d Depth of cut: ap = .010 in
.002
cutting is superior to wet
d Work material: Chromium
d Feed: f =.006 in/rev
.008
molybdenum steel
800
cutting in tool life for
.001
(JIS SCM415), 60 HRC
5.5
d Cutting speed: Vc = 575 SFM
.0008
d Feed: f = .004 in/min
0 BX330 d Depth of cut: ap = .010 in 0 BX360 4 2.5 fracture. .004 400 0
10 20 30 Dry Wet 0 980 1650 2625 3300
Time in cut (min)
3–4