stelliting on Inconel

[smart143]

We are working on an assignment wherein stelliting 6 is required on Inconel pipe N 06625

The process used is GTAW, we are trying with below parameters but obeserving cracks on weld.

preheat: 275 deg C
Interpass: 300 deg C
cooling: wrapping in asbestos blanket.

Need an expert view to get the crack free weld .I tried contacting expert in this field locally, but they are not able to resolve the issue. they only adviced that low thermal gradient is required as material is hard.

Does any body has done similar welding successfully & can share their views.

 

[arunmrao]

Did you provide a buffer layer before attempting to deposit Stellite ?

 

[metengr]

For this type of base material there is no need for a butter layer. The elevated preheat is not needed. I would lower the preheat to 95 deg C preheat, interpass is fine and most important use circumferential stringer beads. Watch your start/stop sequences.