Deoxidation for duplex stainless steel

[Jandyr13]

What is the best deoxidation for duplex stainless steel? And the risering? Is there a formule to calculares the risering for This kind of steel?


Thanks in advance.

Jandyr 13 Foundry

 

[cloa]

You probably need vacuum or inert gas casting- anything that deoxidises would destroy its value as corrosion resistant alloy.

Have you seen this-

http://www.spuncast.com/centrifugally-cast-duplex-stainless-steel.pdf

Risers are probably not relevant.

 

[Jandyr13]

Thank you for your response, but it does'nt help me because we are pouring casting parts in sand moulds so I need to use risers and a good deoxidation to avoid porosity and skrinage. We are using an induction furnace whitout any injection.

Whit the balance of chemical composition we have no problem. The ferrite number is ok and the structure is almost 50/50. The PREN is ok too.

The only problem is porosity and skrinage.

 

[bhollands]

I am assuming you are making CD3MN. We don't change the rigging for duplex stainless steel. Deoxidation is the same as our standard stainless steel. You don't need any kind of inert atmosphere.

What are you starting with? AOD refined ingot or are you alloying up stainless plate? What was your nitrogen content.

Always start with a hot furnace. Wash out before hand with a stainless heat so the furnace and ladle are good and hot. Don't hold the heat in the furnace longer than necessary. Pouring temperature should be as low as you can and still pour a good casting. The furnace should be tapped at a temperature where the metal is ready to pour when it reaches the floor without waiting too long. Duplex is really not that much different than CF8M otherwise.

Bob

 

[arunmrao]

Deoxidation is simple,use mixture of Calcium silicide, ferro silicon zirconium,selenium . Finally purge with argon gas before tapping.

regarding riser selection,use good quality sleeves from Foseco.

How are you adding Nitrogen? Is it with Nitrogen containing L.C.FeCr?

_____________________________________
"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year

 

[Jandyr13]

Thanks for all .

The alloy are CD3MN and CE3MN.

The nitrogen content is .19 and it's adding whit Iron Chromiun Nitro during the melting.

I use magmasoftware to calculate the risering sistem but doesn't work. I concluded that the módulus of sleeves must be the doble than the others alloys.

The deoxidation is a bit of Al, FeSiZr, CaSiMn, Mish, NiMG, Ti and Se. Is there difference to use the deoxidants at ladle instead during the tapping.

A lot of thanks