The inserts are based on a recently developed sintered CBN powder that employs a titanium carbonitride binder substrate (giving high orders of stability), which is then multi-layer coated.
The BNC2010 finish turning grade incorporates seven layers of coating, three are highly secret and each is sandwiched between layers of TiCN in order to create high cutting edge integrity with resistance to flank wear. Finally, the insert is topped with a layer of TiN, which aids surface finish.
The general purpose BNC2020 insert incorporates a high bonding adhesive layer between its CBN substrate and TiAIN layer. It is able to support continuous cutting, as well as light and heavy impact conditions, while maintaining chipping resistance – even when heavy interrupted turning cycles are involved, says Sumitomo.