Browse Prior Art Database

Publication Date: 2016-Dec-12

Publishing Venue

The Prior Art Database

This text was extracted from a Microsoft Word document.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 27% of the total text.


This article discloses a method for fabricating fluidic components such as manifolds utilizing a brazing method.

I.          Background

Fluidic components such as manifolds are often fabricated using the well-known fabrication technique of diffusion bonding.  However, certain disadvantages attend the implementation of diffusion bonding, including requirements on raw materials, limitations on size, and expense.  Further, when employing metal injection molding or a cross-drill method, the size of the manifold is limited by the complexity of the fluidic channel network defined by the manifold and the channel aspect ratio (channel length over channel diameter or depth).  Secondary welding or brazing operations are often required to join fittings to the manifold block.

Therefore, it would be desirable to provide an alternative to diffusion bonding in the fabrication of fluidic components such as manifolds.

II.        Solution

To address the problems discussed above, this article proposes a new brazing method.  The new method utilizes braze foil to join together metal plates (or blocks) that have networks of initially unsealed (open) channel features.  The finished assembly is a metal manifold with channel networks integrated inside the manifold.  The channels may also have openings to the exterior of the manifold providing for connections to other fluidic components.

The new brazing method offers a number of advantages over diffusion bonding.  The method enables the fabrication of manifolds having a larger form factor and more complex channel networks.  The method is simple and flexible.  Finally, the method utilizes starting base materials that are widely available, thereby simplifying the supply chain, reducing manufacturing cost, and allowing for surfaces with higher surface roughness and even machined surfaces to be joined together.

An example of performing the new brazing method to fabricate a manifold will now be described with reference to Figure 1 (below).  Figure 1 is an exploded view showing an example of a thin braze foil (e.g., 0.001 inch thickness) interposed between two metal plates (or sheet metal, or metal blocks), labeled as Layer 1 and Layer 2.  Open channels are formed on one side (i.e., the mating surface or “brazing surface”) of each metal plate according to a desired architecture.  Note that Layer 2 has channel features similar to Layer 1, but these Layer 2 channels are not seen in Figure 1 due to the channels being on the underside of Layer 2.  Figure 2 shows a cross-section of the two metal plates and braze foil to illustrate the channel features in the two metal plates.  Alternatively, the channels could be formed on one plate only or all of the plates and/or could be of partial or full depth (for example, through-etched) into the plate or plates.  The open channels may be any type of feature defining fluid flow paths upon comp...