NTK Cutting Tools

Machine gray cast iron at Speeds Vc= ~ 1200m/min ~ 3900 SFM

Outstanding boundary wear resistance Outstanding thermal shock resistance
Features
  • Superior tool life during high-speed machining due to its wear resistance
  • Excellent thermal shock resistance when turning and milling with coolant
Tooling application

Gray cast iron with scale
Rough Turning/ Milling

Grade map
↑High





SPEED
SX6
HC2 SP9
SX9
HC1,HW2 HC6
CP1
FINISH SEMI-FINISH  ROUGH
FEED

High→

Grade characteristics
Why is silicon nitride ceramic resistant to chipping?

The main component is silicon nitride(Si3N4), which differs from alumina-based materials in that its particles are needle-like.
The intertwining of the needle-like particles greatly suppresses the progression of cracks caused by impact during cutting and prevents chipping.

Gray cast iron roughing application
- - - Scroll the table - - -
ISO Work material Coolant Grade vc (m/min) (SFM) ap (mm) (inch) f (mm/rev) (IPR)
Cast Iron
Rough Turning
DRY/WET SX6 500 – 1200 1600 – 4000 0.5 – 3.5 .020 – .140 0.3 – 0.6 .012 – .024
Brake disc
Material :
FC150
Workpiece condition :
with scale
Cutting speed :
1,100 m/min 3600 SFM
Feed :
0.5 mm/rev 0.02 IPR
DOC :
2.0〜3.0 mm .079 〜 .118 inch
Coolant :
WET
SX6
75 pcs / corner
Competitor’s silicon nitride
50 pcs / corner

SX6 achieved 1.5 times longer tool life compared to competitor’s silicon nitride

Milling Application
Material :
FC270
Cutting speed :
800 m/min (SX6) 2600 SFM (SX6) 140 m/min (Competitor's carbide) 470 SFM (Competitor's carbide)
Feed :
0.06 mm/t (SX6) .0024″ IPT (SX6) 0.20 mm/t (Competitor's carbide) .0079″ IPT (Competitor's carbide)
Feed :
1,400 mm/min (SX6) 55 IPM (SX6)
560 mm/min (Competitor's carbide) 22 IPM (Competitor's carbide)
DOC :
1.5 mm .060
Coolant :
DRY
SX6
360 pcs / corner
Competitor’s carbide inserts
260 pcs / corner

High-speed milling with ceramic significantly reduced cycle time compared to the current carbide inserts. (Single pass process went from 40 min. down to 15min.)
SX6 achieved 1.4 times more tool life.
Tooling costs are reduced by utilizing negative inserts, increasing the number of corners.

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