We manufacture silicon iron anodes by using a metal die (die-cast) that is rotating at several hundred revolutions per minute (rpm) when the metal is poured into the mould. There are three very good metallurgical reasons why centrifugally-cast anodes are superior to die cast anodes:
- For centrifugally-cast anodes, there is no need for any sand cores that have to be used in standard die cast anodes. The sand core acts as an insulator and slows the cooling process so that the advantage of a rapid and one-directional solidification is lost and the internal surface of the die-cast anode is practically identical to an inferior sand-cast anode.
- The centrifugal process allows metal to be poured down a pouring bush into a rapidly-spinning mould and then the pouring bush is immediately withdrawn so that no contact point remains between the anode casting and the supply of molten metal.Only in this way can the centrifugal process eliminate the highly detrimental contact point on the surface of the anode where the metal feed enters the anode, and it consequently results in a metal matrix that is superior to die-cast anodes. If you want your anodes to outperform die-cast anodes and last longer, then buy centrifugally-cast anodes.
- The centrifugal process uses a mould that is spinning at very high rpm’s. This results in forces on the metal that are throwing it against the walls of the mould under very high pressure. These rotational forces are forcing the metal to be compacted as it solidifies so that the microscopic grain structure of the metal matrix is more compact and more homogenous than die-cast items with sand cores. This grain structure means a longer life for the anode and it eliminates the need for adding additional material to thicken the wall of the anode.