OXYTRON from Blasch, silicon carbide in an oxide bond, for auto ladles, heater tubes, nozzles and parts that used to be cast iron.
A ladle that never needs a release layer, an insert that weighs a third of the iron one.
Both come from the same material.
Oxide bonded silicon carbide is non wetting in molten aluminum because the melt meets a surface of silicon carbide grains in an oxide bond of alumina and silica, which aluminum wets poorly at casting temperatures and does not react with the way it reacts with iron. Blasch OXYTRON is completely non wetting in molten aluminum without any surface treatment, so ladles and heater tubes stay free of buildup. The same grade replaces cast iron in wear parts at one third of the weight.
Oxide bonded silicon carbide is silicon carbide whose grains are held together by an oxide phase, mostly alumina with some silica. The SiC grains bring hardness, thermal conductivity and wear resistance, the oxide bond brings oxidation resistance and a surface that molten metal does not grip.
OXYTRON is the Blasch grade: 67% SiC, 30% alumina and 3.7% silica, cast net shape with good dimensional tolerance and a smoother surface than cast iron. How the Blasch process works
Molten aluminum attacks iron and steel: it wets the surface, dissolves iron and builds up oxide and intermetallic layers. That is why steel ladles and tools are coated, and why the coating has to be renewed during production.
Oxide ceramics behave differently. At casting temperatures, molten aluminum wets alumina based surfaces poorly and does not dissolve them. OXYTRON presents exactly such a surface: SiC grains embedded in an alumina and silica bond, with fine pores that the metal does not enter.
The result in production, as Blasch reports it for its DuraLadle auto ladles: no protective layer is needed, ever, aluminum buildup and oxide formation drop, and a ladle runs for months without maintenance.
Values from the Blasch OXYTRON product information sheet.
| Property | OXYTRON |
|---|---|
| Composition | 67% SiC, 30% Al2O3, 3.7% SiO2 |
| Apparent porosity | 14% |
| Modulus of rupture at 2,000 °F | 8,000 psi (55 MPa) |
| Thermal conductivity | 64 BTU·in/hr·ft²·°F |
The modulus of rupture is measured at 2,000 °F, not at room temperature, which matters for parts that work hot. OXYTRON is also oxidation resistant and tolerates thermal shock.
Cast iron wears, corrodes and picks up aluminum; OXYTRON is where most plants start when they stop replacing metal with metal.
Parts for molten aluminum and for wear parts that used to be metal.
Auto ladles for high pressure die casting from 5 to 50 lb, no release layer needed.
Heater sheaths for molten aluminum with long campaigns and less dross buildup.
Thin wall inserts that protect air preheater tube ends from fly ash erosion.
SiClone multicyclone parts that replace cast iron at one third of the weight.
OXYTRON is also used for FGD and spray nozzles, thermocouple protection tubes, abrasion resistant valves and fluidized bed nozzles. For aluminum degassing, Blasch uses a silicon carbide and alumina composite with a non wetting addition; the background is in Improved Ceramic Material for Aluminum Degassing.
OXYTRON parts go to molten metal plants and power generation. Its newer generation OXYTRON 015XDII adds a continuous silicon carbide phase for more erosion resistance, and for the highest temperatures and chemical attack there is sintered silicon carbide.
OXYTRON values and uses: Blasch OXYTRON product information sheet and material page; DuraLadle product sheet; Blasch power generation presentation. Wetting of oxide ceramics by molten aluminum: N. Eustathopoulos, M. G. Nicholas, B. Drevet, Wettability at High Temperatures, Pergamon, 1999.
No. OXYTRON is non wetting in molten aluminum on its own, which is why DuraLadle auto ladles need no release layer at all.
Often yes, and it is the usual first step. It weighs about one third of cast iron, has a smoother surface and holds tighter tolerances.
Yes. Together with NITRON it is used in copper and aluminum alloys for its non wetting behavior and thermal shock resistance.
015XDII is the newer generation, with a continuous silicon carbide phase that raises erosion resistance while keeping the non wetting behavior.
Send the part, the alloy and the cycle. A Blasch engineer checks whether OXYTRON can replace the coated metal part.
