Hi,
I know the two alloys are used for permanent mold castings but not quite sure the difference between the two in terms of castability (foundry preference), casting cost, quality and so on. Appreciate if you could kindly cast some lights on this.
According to my booklet from US Reduction Company, 333 has slightly better fluidity and resistance to hot cracking than 319. So, with certain casting configurations, 333 should cast a little easier, everything else being equal.
Quality is dependent on the individual foundry. Availabilty of the 333 might be somewhat less than the 319, as 333 is derived from Precedent 71A, a proprietary alloy.