The most commonly used powders for porous sintered metals are bronze, stainless steel, nickel- based super alloys and titanium.

The properties of porous sintered elements can be summarised as follows:
* Stability of shape, eg self-carrying structures even at high pressures.
* Good mechanical strength under permanent loads, impact loading or under pressure peaks.
* High temperature strength and thermal shock resistance. Special high temperature alloys can operate up to 1000°C.
* Chemical stability against acids and (alkaline) detergents.
* Wide spectrum of precisely defined pore size distributions: for filters from metallic powders ranging from 0.5µm to 200µm, and from 3µm to 40µm for sintered metal fibre felt.
* Reverse flow, supersaturated hot steam, chemical agents or high temperatures can be applied for cleansing and rinsing.
* Easy to machine, weldable.
As all technologies and products sinter metal filters have also some limits.
Therefore the research is ongoing to eliminate these weak-points.
This in turn has led to the development of the 'metallic membrane' which can be summarised as follow:
* Improvement of the backflushing performance.
* Improvement of permeability in comparison to standard sintered metals filter media.
* Defined particle retention in the lower micron range.
* Possibility to extend the typical applications for sintered metal filters using the new powder metallurgy approach in the area of the micro filtration.

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GKN Sinter Metal Filters GmbH is based in Radevormwald, Germany. www.gkn-filters.com