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In dieser Arbeit wird der Einfluss der Herstellungsbedingungen und -materialien von Metall-Keramik-Verbundschichten auf die strukturellen Eigenschaften der Schichten untersucht und optimiert, um insbesondere die mechanischen Eigenschaften zu erhöhen. Dabei erfolgte die Abscheidung der Metall-Keramik-Verbundschichten durch eine Verfahrenskombination von elektrophoretischer und galvanischer Abscheidung unter zu Hilfenahme von Siloxan als Bindemittel. Es konnten somit Schichten mit einem hohen Keramikgehalt erfolgreich hergestellt werden. Als keramische Komponenten wurden kommerzielle Siliciumkarbid-und SiliciumnitridPartikel eingesetzt. Als metallische Komponenten um die poröse keramische Schicht aufzufüllen und die Struktur zu festigen, kamen Nickel bzw. Kupfer zum Einsatz, wobei eine Vorvernickelung bzw. Vorverkupferung des Stahl-Substrats (X6Cr17) erforderlich war, um die gewünschten Eigenschaften hinsichtlich der Haftfestigkeit der Schichten zu erhalten. Die Charakterisierung erfolgte mittels optischer Mikroskopie und Raster-und Transmissionselektronenmikroskopie (REM, TEM), wo besonders die Ausbildung der Verbindung der einzelnen Partikel durch das Siloxan deutlich wurde.Schlüsselwörter: Elektrophorese, Metall-Keramik-Verbundmaterial, Rasterelektronenmikroskopie, Transmissionselektronenmikroskopie The influence of the formation process and used materials of metal-ceramic coatings on the structural properties of the deposited layers were investigated and optimized to increase the mechanical properties. There the deposition of the metal-ceramic-layers occurred by a combination of electrophoretic and galvanic deposition with siloxane as bonding compound. Layers with a high ceramic content were successfully created. As ceramic components commercial silicon carbide and silicon nitride were used. Nickel and Copper respectively were applied as metal component to fill the porous ceramic structure with the aim to increase the strength of the layers, where nevertheless a pre nickel-plating or pre cupper plating of the steel substrate X6Cr17 before ceramic component deposition had to be done to increase the adhesion of the layers. The layer characterization was made by optical microscopy and scanning and transmission electron microscopy, where especially the bonding of the single particles by the siloxane was in evidence.

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Glass fibre composites subjected to hot water exhibit a reduction in stiffness and strength owing to a combination of matrix plasticisation and fibre/matrix interfacial degradation. If the composite system is subjected to some form of mechanical damage such as cracking from an external impact, the net consequence of water exposure is more difficult to predict.This paper reports on the effects of water exposure at two temperatures (65 and 93°C) on non-crimp, quadriaxial, glass fabric systems with a polyester matrix. The residual properties are measured using the compression after impact test. It is shown that the residual properties of laminates tend to reach a minimum plateau after extended exposure to water, the value of which is dependent on the temperature of the water. It is also seen that the effects of impact damage vary depending on whether or not the impact is experienced before or after the water exposure. Impacting after conditioning produces a greater density of through thickness damage, which results in a lower compression after impact strength than impacting before conditioning.