Superheat for pouring Cerrotru (Mp=281*F (eutectic)) 1

[NickE]

I am going to pour a Silicon RTV mold with Cerrotru. This is a Bi-Sn eutectic, with the Mp@281*F. The shape is approximately a hollow cylinder enclosing around 160in^3. Should be 50lbs + gates/risers of metal.

I didn't design the mold, its not optimal. Though it should work. There is one spot where I'm worried about a cold shut. I want to get enough superheat to fully fill the mold, but also dont want to wait all night for shakeout....

Thanks for any tips and tricks... I studied GCI Casting in grad school, so I have some experience with casting, however there is a huge difference btw pouring a melt at 2600F vs 300F, also RTV is a bit different than green sand.


Nick
I love materials science!

 

[unclesyd]

When using the Cerro Alloys we always started with a superheat of 35F above the melting point.

Remember that that these alloys are very poor heat conductors so if you start with enough metal to make a continuous pour I don't see a problem. We cast some very intricate parts of about half your size with no problems.

Depending on the mold composition you might be able to do a little preheat.