Author: Susanne Freund

Ceramic solutions for foundry industry

4.4.2018

© Fraunhofer IKTS

Porous ceramic inserts for local reinforcement of light metal and gray iron castings.

Foundry industry has a key role as supplier especially for companies in automotive and plant engineering, aviation industry, shipbuilding or energy technology. The requirements for the production of castings with regard to quality, price structure, reliability and shape variety increase continuously. Fraunhofer IKTS develops advanced ceramic materials which may significantly contribute to satisfy these demands.

Ceramic protection plates for long-term stable dross separators

During casting processes, dross separators must be replaced quite often due to fast corrosive and mechanical wear. Dross separators with integrated protection plates made of silicon nitride – which shows excellent mechanical and corrosive stability – can significantly extend the maintenance intervals and thus reduce costs for foundry plants.

 

Gas-permeable ceramics for stabilization of plant components 

In metallurgy and metal processing industry, gas-permeable ceramics can help to release expanding gas and thus to avoid overpressure at function-critical components such as guide rollers. Additionally, they can serve as an active safety device preventing extreme pressure increase, deformation or even bursting. Furthermore, gas-permeable ceramics can be used to generate and distribute microscopically small gas bubbles in melts very homogeneously.

 

Cost-efficient ceramic filters for melt cleaning

High-temperature-resistant ceramic foams made of zirconia are used in foundries to clean steel melts from non-metal inclusions, such as slags, molding sand residues and deoxidation products. By means of a new material concept, where 65 % of the original zirconia powder was replaced by a stoichiometric mixture of alumina and zirconium silicate, the production costs for these filters could be reduced by 40 %.

 

Ceramic molds for improved cooling processes in castings

The thermal conductivity of casting molds directly influences the microstructure of the casting. Casting molds consisting of an optimized combination of silicon carbide and innovative binders provide faster heat removal from the castings. Thus, microstructures that are optimized for the specific application can be realized.

 

Porous ceramic inserts for highly stressed light metal and gray iron castings

By means of porous ceramic inserts, light metal and gray iron castings can be locally reinforced in thermally and mechanically high-stressed areas. Not only can the robust preforms be produced simply and inexpensively in high quantities, they also have a special material surface, which supports an excellent interlocking of ceramic and metal surfaces.