We are turning the OD and boring the ID of SYMN SCS-610-6 bronze bushings and getting quite a bit of wear on every insert (carbide) we have tried. Would ceramic or CBN or diamond be an option? What is working best right now is a DCLNR holder 431KC5010 insert at 200 surface feet for the OD (finishing) and SCLPR holder 2150KC5010 at 100 surface feet for the ID (1/2 inch boring bar finishing a .7500 hole 3 1/4 deep). We are not taking a lot of material off, the busing is near net shape, but constantly adjusting for wear. We are making it work but looking for a better solution. Machine is a Doosan Puma lathe, plenty stout enough for this size work (1 1/4 OD) . We turn lots of A-2 and D-2 and don't have the wear problem that this bronze gives us.
How different is this from oilite?
Oilite recommends PCD-Diamond.
https://oilite.com/best-machining-practices (I think they meant inches per turn, not inches per minute)
Also you should be using a high positive rake insert/holder. Negative rake tooling on impregnated bronze just closes all the pores.
But honestly a sharp carbide insert should be sufficient. When we did shaft bushings for ships it was primarily just brazed carbide in the turning centers and lathes, although the edges were sharp and polished enough you could cut yourself with them.
How much are you taking off in roughing and finishing passes?
How much wear are we talking exactly? Comping every other part? Every 100th part?
You make it sound excessively bad, but something can't be right. We machine down 86# blocks of G10/FR-4 to about 12# (lots of internal removal) and the uncoated carbide cutters last about 3 parts before they need to be resharpened. It's a solid 2+ hours of non-stop cutting per part.
While I was pondering. I did look up the standards for both.
Oilite: SAE 660 (Al/Sb/Cu/Fe/Pb/Ni/P/Si/S/Sn/Zn)
610-5: SAE 841 (
https://www.avivametals.com/products/sae-841-sintered-bronze-oil-impregnated) (C/Cu/Fe/Sn)
Metallurgically speaking, this stuff should be noticeably softer than Oilite/C93200.