Machining performance of CBN inserts for hard turning bearing

The two main application areas for CBN inserts include

1.Turning hardened steel

2.Turning gray cast iron

Now we will introduce the application of cbn insert on hard turning hardened steel part---bearing steel .

Normally CBN only works when the steel component is hardened(which means through heat treatment), with a hardness above HRC50. In its original state, thse material is usually around 250 HB, but the hardness is increased significantly through deformation hardening when used, without any loss of toughness.The hardness is also very difficult to measure with high accuracy due to the high level of work hardening.

The deformation hardening will affect the material also during machining, and this impacts the selection of cutting tools materials which can be used for machining.

Cutting data when using carbide insert has to be very low. Normally, the cutting speeds can be range 20 to 30 m/min. But if with CBN insert, cutting speeds can be increase to 200m/min, which significantly improve the processing efficiency.

One typical application Case as follows: Halnn CBN inserts has a long experience and has been very successful on hard turning hardened steel Bearing steel.

Machining Part：Bearings Machining Materials:GCr15                                                                                          WorkpieceHardness:HRC62                                                                                                              Inserts Grade:BN-H11 DNGA150408                                                                                      Cutting Type: Dry Cutting                                                                                                        Cutting Parameters: ap=2.5mm,Fr=0.12mm/r,Vc=140m/min
Inserts Materials	Linear Speed(m/min)	Lifetime/cutting dege	Surface Roughness
Halnn BN-H11	140	12	Ra0.8~1.6
Imported PCBN inserts	140	10	Ra0.8