Ceramic foam filters

Ferro-Term has the plesure to offer to all quality-oriented and cost conscious foundries Cerferr CERAMIC FOAM FILTERS SiC+Al2O3 based for cast iron and Al2O3 based for aluminum and copper alloys.

The use of silicon carbide and special aluminum oxide for their production ensures their resistance to thermal shock and dimensional stability during the flow of liquid metal.

  • Filters for iron

  • Filters for aluminium

  • Filters for steel


For over 15 years our ceramic foam filters are appliied in many domestic and foreign foundres. Reliable manufacturing process provides high quality product and ISO 9001:2008 certyficate confirms application of high standards.

Certificate ISO 9001:2008

Product line

We produce square, rectangular and round filters of dimensions required by the client and porosity 10 and 20 ppi (por per linear inch). There can be produced filters of porosity ppi 30 at special customer's request.

Rectangular filters
Round filters
40x40x15 4-5 810
40x40x20 40x20 4-5 648
50x50x15 5 525
50x50x20 5 420
50x50x22 50x22 5 385
60x60x22 60x22 6 405
75x50x22 7-8 378
75x75x22 70x22 7-8 252
100x75x22 8-10 180
100x100x22 100x22 10 135

Table 1. Recommended sizes


Compact, short and direct gating system.

Larger pattern plate area available.

Significant reduction of non-metalic inclusions due to high filtration efficiency (such as slag inclusion and sand holes from moulding sand).

Improved technical properties of castings.

Reduced casting costs due to increased yield resulting from a smaller gating system and reduced number of wastes.

Reduced machining costs due to improved worability, reduced machining time and reduced wear of cutting tools.


Material ██ Especially recommended
porosity of filters
■ recommended filter's porosity
10 ppi 20 ppi
aluminium alloys ██
grey iron ██
ductile iron ██
Malleable iron ██
Copper alloys ██

Table 2. Recommended porosity

Filtered metal
max || kg/s
(10 ppi)
Grey iron Ductile iron Grey iron Ductile iron
65 32 4 3
100 50 6 4
220 110 14 9
300 150 18 12
400 200 25 16

Table 3. Recommended permeability



Excessive reduction in filter thickness is not recommended as this impairs the collection of smaller impurities in the filter pores. Greater thickness means that metal has to displace (travel) in pores a longer way and more often changes flow direction, which improves metal clearing. The filter thickness also directly effects its mechanical strength which is especially important for large filters.


Values in table are for information only since depend on the degree of impurity in liquid metal, its temperature, metallostatic pressure, the shape of the casting system etc. They should be verified in the actual foundry conditions. Under extreme conditions as much as 50% drop in flow capacity may be encountered.

First application

As a rule, for foundries which have no experience with the use of filters, we recommend to begin with ppi 10 porosity filters. The thickness of the filter does not basically effect flow capacity, however, flow velocity will be greater for thinner filters.