Frost resistance of ceramic building materials - Factors of influence, standards and new test methods (Part 1) [Frostbeständigkeit von keramischen Baumaterialien - Einflüsse, Normen und neue Untersuchungsmethoden (Teil 1)]
Teichgraber M.,KI Keramik Institute GmbH |
Petzold J.,KI Keramik Institute GmbH
ZI, Ziegelindustrie International/Brick and Tile Industry International | Year: 2013
This contribution provides information on major methods of characterizing the frost resistance of ceramic building materials. Testing is performed according to the standards-compliant, product-specific method of frost simulation in refrigeration units, e.g., in chest freezers. A test method devised at Kl Keramik-Institut GmbH allows supplementary quantification of how product modifications and changes in technology affect frost resistance, independent of any defects established via frost simulation. Part 1 surveys the basic principles and applicable standards. Part 2, in which the test results will be presented, is scheduled to appear in Zi5/2013.
Impure raw materials as a source of defects in building ceramics - Analysis with scanning electron microscopy [Verunreinigte Rohstoffe als Fehlerquelle in der Baukeramik - Analyse mittels Rasterelektronenmikroskopie]
Graf M.,KI Keramik Institute GmbH
ZI, Ziegelindustrie International/Brick and Tile Industry International | Year: 2014
This paper provides an insight into analysis methods with the use of scanning electron microscopy. The setup and operating principle of the scanning electron microscope (hereinafter referred to as SEM) are described and the interaction between the electron beam and the specimen are explained. Based on three examples, two instances of efflorescence on natural red clay roofing tiles and coarse components as the cause for spalling, the procedure and possibilities for analysis with the SEM are illustrated.
Graf M.,KI Keramik Institute GmbH |
Schulle W.,KI Keramik Institute GmbH |
Hohlfeld K.,KI Keramik Institute GmbH
Keramische Zeitschrift | Year: 2012
The quality and usefulness of high-alumina refractory products are mainly determined by the characteristic properties of the binder phase between the grain structure. Based on this fact a mullite crystalline binder phase should be developed with especially acicular mullite crystals which grew up partly of the grain structure. The present studies describe the development, evaluation and testing of such a mullite binder in several model bodies.
Bartusch R.,KI Keramik Institute GmbH
Keramische Zeitschrift | Year: 2010
The article gives a short overview of the current status and some trends of extrusion technology in the field of technical ceramics. The screw extrusion machines are still dominant in the ceramic production. These machines equipped with the latest measuring and control technique generate very high flow pressures up to 25 MPa. Due to the intensive development work the number of the piston extruder has been increased significantly during the last decade. The specifics and features of both basic types of extrusion machines are explained and compared.