Hard face over alloy 625 weld overlay

[Ratheesh_n]

Members,

We have a case of valve disc material F44 and its weld overlaid with alloy 625(NICrMo3) and followed by weld overlaid with Stellite 6. Is it a recommended method to follow and what must be the reason for doing the corrosion resistance overlay before hard facing.

 

[EdStainless]

F44, as in S31254?
This alloy has more corrosion resistance than the 625 does on most environments.
The only reason that I can think of is that the 625 is a stabilized alloy and will resist formation of carbides in the weld.

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P.E. Metallurgy, consulting work welcomed

 

[Ratheesh_n]

@ Ed Stainless yes S31254.