4140 hardfacing

[claritysable]

gday i need to know if i can hardface 4140 tube , preferably by nitriding , not welding , to about 70 rockwell c , i need to make stunt pegs for bikes , and its gotta be hard so it wont wear bugger all , but not to hard that it will seperate and crack off , any help would be great thanks , daniel

 

[gr2vessels]

G'day mate,
Please read below:

"4140 hardened and tempered bar can also be successfully nitrided, giving a surface hardness of up to Rc 60. Nitriding is carried out at 490 oC - 530 oC, followed by slow cooling (no quench) reducing the problem of distortion. Parts can therefore be machined to near final size, leaving a grinding allowance only. The tensile strength of the core is usually not affected since the nitriding temperature range is generally below the original tempering temperature employed".

However, I don't reckon you can do that on a tube without bugger it all together, disorted and brittle like glass..

Cheers,
gr2vessels