Material for aluminium melting crucible 1

[arunmrao]

I have been asked to cast 100 and 250 kilos capacities crucibles for melting aluminium alloys. Normally it is made in grey iron,but now I have been asked to improve the life of this crucible by suitably modifying the alloy,but cost is an important criterion.

I am considering to cast it with 4-5% Silicon and 0.5-1% Molybdenum. I shall be thankful if some one can share their experiences.

 

[kclim]

what's the degradation mechanism?

 

[sbi]

Why dont you go buy a silicon/carbide crucible?
molten aluminum is quite corosive to cast iron
we use 3 sizes in our shop, 30K, 100K & 680Kilo aka 1500 lbs
the 100K (220lb) is in are induction melt furnace and we get over 750 heats out of one

Vesuvius is one of the largest supplers world wide with sizes from 1 kilo to 1000K

Bill Loutzenheiser VP-CTO
Phoenix Castings
Central Nebr., USA

 

[arunmrao]

It is not my intent to use a CI crucible. I have been asked by a die casting manufacturer to supply CI crucibles with a better life. I am aware of iron pickup and related issues. I have as yet not responded to this RFQ.

The practice that I have noticed here is that quite often they use CI crucibles in their holding furnace.

 

[sbi]

as I stated be fore you should talk to Vesuvus
since you are only melting 250K ( 550 lb) a crucible would be the best, they make then in clay grafite, and silicon carbide and even son ceramics
the manufacture canbe the best source of info for your problem

Bill Loutzenheiser VP-CTO
Phoenix Castings
Central Nebr., USA