Metallising Processes

We utilise thick and thin film technologies in our refractory metallising, applying proprietary inks and coatings to our ceramics according to individual customer requirements. Whether customers require an electronic circuit path or joining a metal component with ceramic, our metallisation, brazing and joining experts help you select the most effective and cost-efficient materials and bonding methods.

Refractory Metallising

Using a coating of molybdenum based paints followed by nickel plating, an interface can be provided that enables ceramic/metal assemblies to be formed by brazing providing joints that are hermetically sealed. A layer of molybdenum-manganese is deposited with a typical thickness of 10 to 30 µm after sintering. The metallisation sintering process is carefully controlled to achieve a balanced mixture of Molybdenum particles surrounded by a matrix of glass to ensure high bond strength between the metallised layer and the ceramic base.

A range of deposition methods are available depending on the geometry of the component, including:

• Screen printing
• Pad printing
• Brush coating

For cylindrical ceramics, a proprietary automated deposition method delivers consistent uniformity of bandwidth and coating thickness. A thin layer of nickel, typically 3–5 µm, is electrically or chemically deposited on the Molybdenum-Manganese layer to achieve the required wettability for subsequent brazing.

Thick Film Deposition

This involves precious metal pastes, resistors, dielectric insulation layers and sealing glass.

The application of thick film inks provide the engineer with amazing versatility in the use of ceramics. Brushed or screen printed these inks are fired onto the ceramic at 850° providing a secure interface. Inks are supplied in a variety of different materials including gold, silver, copper, glass, dielectric and a range of resistive inks. Nominally 10 microns thick per application, thick film inks can be applied in multi layers to increase coating thickness as required. Gold layers can be wire bonded and silver layers can be soldered.

Typical Thick Film Deposition Applications

• Instrumentation
• Control systems
• Guidance systems
• IR and UV detectors
• Circuit boards
  
  

Thin Film Deposition

In some cases it is necessary to apply a thin metallised layer to ceramic surfaces for discharging or electrical field generation. A range of coatings are available including aluminium, gold and titanium at typically 1-2 microns thick. Virtually any patterns can be applied and layers are even and consistent. Multi layers of differing materials can be applied such as nickel chrome and nickel gold. This process does allow subsequent electroplating should there be a requirement. Physical vapour deposition, or PVD, is used to apply thin metallisation or coating to fully dense ceramics.

Quality and process control is a critical feature of our processes which ensures you receive a consistent and reliable product at all times.