Inmatec Technologies GmbH, Rheinbach, and Fraunhofer IKTS, Dresden, Germany, have partnered to test the extrusion of rods and pipes from Inmatec’s INMAPOM K3012 Ceramic Injection Moulding feedstock.
The test results reported that the extruded green parts were extremely dimensionally stable and can be mechanically processed in various ways. The testing showed that even advanced extrusion applications are possible with the ceramic feedstock INMAPOM K3012.
Round rods of solid material up to 15 mm in diameter can be extruded to lengths of 4000 mm. The extrusion of pipes with 1 mm wall thickness and the same outer diameter is also possible over this length. The rods and tubes cal also reportedly be easily mechanically machined: cut to size, but also modified by drilling, milling, turning and thread cutting.
The variety of finishing options enables the production of more complex ceramic components from the long, uniaxial green bodies. For example, the blanks can be provided with cross or oblong holes and graduated axles, feed screws and screw flights can be turned in. Sharp-edged spigot ends can also be produced. This way of manufacturing is particularly suitable for smaller series, but, if the batch size is so small that costly tool design is not worthwhile, mechanical machining of the extruded green parts is thought to offer an efficient and economical alternative.
The use of INMAPOM K3012 is said to not only open up possibilities in green machining but also offer good properties for the finished parts. Zirconia components can be produced from Inmatec’s standard feedstock that is resistant to high temperatures, aggressive atmospheres and extremely durable. Ceramic axles, augers or spindles can be used in environments where other materials might fail; they also outperform some superalloys in terms of wear resistance.
Green parts from INMAPOM feedstocks are catalytically debinded in just a single step. The POM-based binder developed by Inmatec can be completely removed within twelve hours in a nitric acid atmosphere. The subsequent sintering is carried out at a temperature of 1500°C. To further improve the mechanical properties of the components, additional densification by Hot Isostatic Pressing (HIP) is also possible, enabling them to withstand high loads.