When injection molding abrasive materials such as glass fiber-reinforced plastics (GFP), metal and ceramic powders, hardened steel molds already show signs of wear in critical areas after a relatively short time. To process such materials reliably and economically, the mold inserts must be wear-resistant. Because of their exceptional tribological characteristics, high-performance ceramics are especially well-suited for such applications.
However, the wear and corrosion resistance of the ceramic can be exploited only if the thermal expansion and thermal conductivity are matched exactly to that of the steel. In addition, it must be possible to process the ceramic by means of EDM. Finally, the addition of electrically conductive material must not compromise the strength and toughness. Until now, no material was able to meet these requirements.
Now, however, a new formulation is available to fill this gap. "Dimacer" high-performance ceramic is based on an aluminum oxide matrix containing vol.% of titanium carbide particles as the electrically conductive component that is added to metastable tetragonal zirconium dioxide co combat embrittlement. According to information from the manufacturer, the strength and toughness of the conductive, and thus erodible, ceramic is equivalent to that of the undoped material.
Possible applications include mold inserts for processing GFP as well as powder injection molding, production of injection molds for miniature and micro parts, and inserts in extrusion dies. Regardless ff the application, the material will extend the service life several times.
|© 2013 by Carl Hanser Verlag|