Bonding stellite 6 to alloy steel
Bonding stellite 6 to alloy steel
(OP)
Our wps states a preheat of 500 F we have maintained that. With a maximum 650 F interpass temp. we have maintained that. minimum 2 layers of overlay. why are we getting cracks in the second layer? not the first. tig process,1/8" filler.





RE: Bonding stellite 6 to alloy steel
RE: Bonding stellite 6 to alloy steel
RE: Bonding stellite 6 to alloy steel
RE: Bonding stellite 6 to alloy steel
RE: Bonding stellite 6 to alloy steel
We built an insulated box with a piece of grating to place the parts on for welding. There were heaters inside the box and we applied heat from the top also. As you know, at 1000 F, the c.s. parts are red. The welders wore insulated suits with forced air cooling. GTAW process.
A preheat of 500 F is a minimum preheat, but, it won't garantee crack free deposits.
I have heard an outfit in France is achieving crack free Stellite 1, but, to date I haven't been able to do so.
RE: Bonding stellite 6 to alloy steel
We had a local machine shop that did HP steam turbine part repair work for us and they were able to deposit Stellite 6 on Grade 22 substrate using a 600 deg F preheat with Inconel butter. These were GE, HP steam turbine startup, by-pass valve discs. There were no problems, the trick was bead placement and avoiding interruption of GTAW welding.
RE: Bonding stellite 6 to alloy steel
In our case no butter layer was allowed. The harface was deposited directly on the substrate.
RE: Bonding stellite 6 to alloy steel
RE: Bonding stellite 6 to alloy steel
YES. Make sure they use Liquid penetrant inspection and not a magnetic particle examination. What you are viewing is the break in the applied magnetic field causing the particles to line up.