Special material needed which can be core hardened to 30-35 HRC and then surface hardened to around 55-62 HRC

An industrial unit needs to design a Micro Boring Head with a special material which can be core hardened to 30-35 HRC and then surface hardened to around 55-62 HRC. A Micro Boring Head is used in milling machines for making precision bores. These are used mainly in automobile, aerospace and pharmaceutical industry. A stronger, sturdier material will be better equipped for high speed machining, giving better surface finish, where spindle speeds can reach well above 3000-4000 RPM. Most of the Italian and German brands use special material for achieving this hardness.

Currently the industrial unit is using EN8D and achieving core hardness of 25-28 HRC by oil quenching and tempering. Industrial unit has outsourced it to an established PTL (Mahindra) vendor locally.

Industrial unit got it touch with a Swedish company called Uddeholm and they offered below solution.

“It was nice talking you over phone regarding our grade Bure, as discussed we are attaching herewith the catalogue of Uddeholm Bure for your ready reference.  We will supply this grade in soft conditions (18-19 HRC), you can achieve up to 52 HRC after vacuum heat treatment.  “

Please let us know if you are aware of any material which can be used in this case and more importantly if it can be procured locally. we would also need to understand the heat treatment process for the same.