VTT cluster diamonds

Many years of scientific research have demonstrated the useful properties of cluster diamonds for a wide range of materials. The results of this research represent a milestone in modern industrial development.
The addition of specific cluster diamond suspensions to plating processes will make radical changes to gold, silver, chrome, nickel, zinc and other surface coatings. The wear resistance of the coatings will be improved and their structure will be homogenous. The thickness of the coatings can be reduced without impairing the protection they offer against wear.

Below is an example of the impact of cluster diamonds in a gold coating:

Gold is used in a wide range of industrial applications. Its high level of chemical resistance, its excellent thermal and electrical conductivity and its superb polishing properties make gold an important material. The major disadvantages of gold include its low microhardness and low wear resistance.

Electrochemical processes are generally used for gold plating. Cobalt, nickel, antimony, silver, copper and indium salts are generally mixed with the electrolyte to improve the microhardness and wear resistance of the gold. However, this can lead to problems with the composition of the electrolyte and to major technical difficulties with the coatings and the recovery of the electrolyte. One particular disadvantage of this process is the change in the electrophysical properties of the gold coating.

In order to avoid these problems, the cluster diamond coating was developed, which consists of fine diamonds as well as gold. The process involves precipitating the tiny ultradispersed diamonds together with the gold onto the surface of the matrix to form a metal coating with a special structure.

The benefits of the cluster diamond coating compared to standard processes include:

• Increasing the wear resistance of the gold coating by between three and ten times when compared to pure gold and by two to three times when compared to the traditional gold/nickel coating.
• Increasing the adhesion of the coating by 20 to 30%.
• Improving corrosion resistance by reducing porosity.
• Making more efficient use of the electricity and materials.
• Removing the need for additional processes, such as high-gloss polishing, after the electroplating process.
• Reducing the overall gold consumption.
• Reducing the thickness of the coating whilst guaranteeing its quality.
• Increasing the fineness of the gold in the coating.

Cluster diamonds are used in the following areas:

• Lubricants
• Polymers and rubbers
• Polishing and lapping agents
• Electroplating
• Grinding agents