Potential Applications & Benefits of Diffusion Bonding - Conformal Cooled Molds

  • Date: May 16, 2017
  • Time: 2:00 PM
  • Room: Calhoun Salon

Joining represents one of the most crucial and demanding manufacturing steps during the transfer of new conformal cooling designs into real molds. In many cases geometrical limitations, e.g. maximum size and/or cooling structure complexity, have to be considered when conventional manufacturing ways are followed.

Joining processes in modern Hot-press Furnaces possess a huge potential to enhance both the design flexibility and mould reliability. Additionally the joints reveal excellent mechanical properties. Joint strengths, nearly as high as the base material, can be reached. The elimination of any filler material is the most important feature for design flexibility. The fused mold construction exhibits homogeneous properties without any macroscopic interfaces. This results in a cavity or core surface that has no witness lines which is a desirable feature for products like lenses.

In the past, bonding machines combined small pressing plates and a low degree of processing precision and repeatability. Thus industrial implementation stayed mainly limited to research and special applications. However, nowadays it has become possible to construct machines with pressing plates exceeding: 39.4" D x 35.4" W x 17.7"H (800mm D x 600mm W x 450mm H) with a size of 39.4" D x 39.4" W x 19.47 H (1000mm D x 1000mm W x 963mm H) coming soon.

Also the monitoring and control technology has increased considerably, resulting in significant improvements in reproducibility.

This talk will present a comprehensive overview of the-state-of-the-art of available hot-press machine concepts and the most important process-related parameters for industrial scale production. Advantages given by these unique joining procedures will be described on actual bonding applications in research and industrial production. In addition, a comparison of vacuum brazing and diffusion bonding will be given, from the technical and commercial point of view. In the closing part of the presentation, an outlook will be given on some future manufacturing ways, by using the full potential of the diffusion bonding possibilities.