In addition to Container and Apparatus Construction, there’s another production process that is ongoing on the Thale site today: powder metallurgy. From 1939 onwards, Friedrich Eisenkolb built a research and testing facility on the site. One major goal was to prepare for war production. For example, the rotating bands on shells were made of bronze. The challenge was to find a way of making them from cheaper raw materials, using a more effective process. In that, Eisenkolb was successful.
In powder metallurgy, the starting material is iron powder. This was initially produced in what’s known as Hametag Vortex Impact mills. Later, it was made by atomisation using compressed air or water – and that is still the current method. The iron powder is usually mixed with alloy powder and then filled into the metal press from above. The press works with short cycles, in other words, it quickly produces large numbers of mouldings, which move down the incline and out of the unit.
At first, the pressed parts aren’t very strong. They are strengthened by means of subsequent heat treatment known as sintering. Sintering is carried out in special furnaces in an inert gas atmosphere, where the parts gain the required strength at temperatures of up to twelve hundred degrees Celsius. After sintering, the parts are often calibrated, in other words, re-pressed to achieve greater precision.
If you turn around, you’ll get an idea of the ready-to-install components that were manufactured in Thale during GDR times: fittings, locks, bearings, sewing machine parts... and the star-fish shaped centrepiece from the lock of a Trabant car!
All depictions: © Hüttenmuseum Thale
