Casted Replacement for 4340 Nitrided Component
Casted Replacement for 4340 Nitrided Component
(OP)
Hi All,
Currently we have a part that is 4340 hardened to 36HRC and gas nitrided. A needle bearing rides on the surface of the component and requires high hardness and great surface finish. We are thinking of switching this component to a casted part to save a lot of time and cost on machining. Can anyone recommend a suitable alloy that is ideal for high strength and is compatible with nitriding? It is likely to expect that the toughness and fracture toughness of the casted component will be lower?
Thanks,
M
Currently we have a part that is 4340 hardened to 36HRC and gas nitrided. A needle bearing rides on the surface of the component and requires high hardness and great surface finish. We are thinking of switching this component to a casted part to save a lot of time and cost on machining. Can anyone recommend a suitable alloy that is ideal for high strength and is compatible with nitriding? It is likely to expect that the toughness and fracture toughness of the casted component will be lower?
Thanks,
M





RE: Casted Replacement for 4340 Nitrided Component
RE: Casted Replacement for 4340 Nitrided Component
RE: Casted Replacement for 4340 Nitrided Component
RE: Casted Replacement for 4340 Nitrided Component
RE: Casted Replacement for 4340 Nitrided Component
This is likely, how much lower depends on material choice and processing options.
rp
RE: Casted Replacement for 4340 Nitrided Component
RE: Casted Replacement for 4340 Nitrided Component
It is unlikely you will obtain the same cleanliness and grain microstructure quality in any casting that you are getting in the wrought 4340 material. With regards to fatigue life of a rolling element bearing race surface, these characteristics are of significant importance. I would recommend taking a careful look at the reduction in calculated adjusted life you will see with your bearing by switching from a wrought material to a cast material for the race. The difference in material reliability factor between a cast and a wrought material could make a difference of anywhere from 2X to 4X (or more) in the calculated adjusted life of the bearing system.
Hope that helps.
Terry