Plated CBN wheels - How increase life?

[Biffi]

I'm working with cilindrical plunge CBN operation, and we achieved bad results in wheel life (less than 50.000parts/wheel). The axial/radial runout is under 0,005mm, straight oil, work material = superalloys (nikel), grit size = B251, stock 2mm, cycle time=6sec, roughness tolerance 2Ra. Does anybody knows how to improve wheel life, keeping roughness and small cicle times?
Biffi

 

[genagur]

What wheel have you been using? What is the spec? Is such short whel life caused by frequebt dressings? How many workpieces can you grind between two dressings?
I would suggest to try a extra-high-porous vitrified cbn wheel. There was an article on those wheels in the European Tool and Mould Making Magazine in the October Issue, page 24. If you can't find it, write me and I will send you a PDF copy. These wheels were specially developed for use on "nimonic" nickel-based alloys.
gurinovich@abrazive.spb.ru

 

[Biffi]

genagur,
i'm using electroplated CBN wheel (single layer) - specification B251. I don't know the concentration (supplier usually don't say it). There no dressing for this kind of wheels.
Thanks for the sugestion, I will check if I can finf this paper.

 

[upadra]

hi biffi,

this could be due to the monocrystalline cbn used in the wheel. i would recommend using a high toughness polycrystalline cbn (like borazon cbn 570). talk to your supplier about it.