Material to replace 440C…

[quizzical1]

Hi All,

Is there a metal that we can switch to that is easier to machine than 440C and then hard coated to 55-59 Rc?

 

[TugboatEng]

Do you need surface hardness? Do you strength? Do you need corrosion resistance?

 

[EdStainless]

More info please !!
What size are the parts?
What is the service?
Any bulk loads?
How are you making the parts?
Rough machine in annealed condition and then Q&T and then finish grind, I hope?

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P.E. Metallurgy, consulting work welcomed

 

[quizzical1]

sorry guys....

1" diameter CNC turned / bored shaft in annealed condition then post hardened and electropolished.
used with exterior ball bearings that position and allow the shaft to roll linearly similar to Thompson Linear roller bearings.

Current complaint is the machining is too difficult - strength is not a real concern (similar to 303SS is fine) but require hard surface to prohibit brinelling of the ball bearings.

corrosion resistance similar to 303 SS is fine

 

[EdStainless]

How about 440A or B?
Or one of the other martensitics such as 410 or 420?
You could low temp surface harden any of these.
I have also seen TiC surface treatment used. The Ti bearing gas reacts with the C in the alloy to form the hard surface.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed