What is Electrojoining
A common task in engineering - to permanently and hermetically join two or more components (such as attaching flanges to bellows expansion joints) - is often accomplished by welding, brazing or soldering.
However, this becomes challenging, costly or impossible when:
- One of the articles being joined is made of a material that can not be welded and/or soldered.
- The presence of solder in the joint is unacceptable.
- An item is too thin for welding.
- One of the items is non-metallic.
Adhesives can be used in such cases, but then the joint does not provide electrical or thermal conductivity, and often is not as durable and mechanically strong as a metal-to-metal joint.
Electrojoining is an electroforming-based joining technique in which two or more items are permanently and hermetically bonded together by a tightly adherent electroplated layer. Exceptionally strong mechanically, such joints, when properly executed, are also air- and helium-tight, and have excellent thermal and electrical conductance.
The added benefits of this joining method (also known as 'cold welding') are:
- low (<120°F/50°C) temperature of all operations - no heat affected zone that compromises metal strength after welding or brazing
- a choice of materials that can be used in the joint - NiColoy®, Nickel, Copper, and their combination
- electroforming and electrojoining can be performed simultaneously, reducing the cost of assemblies
- components being joined can be accurately aligned prior to electroforming, eliminating the need for additional fixturing
- ability to join dissimilar or non-conductive materials that are impossible to weld, solder or braze
- ability to hermetically join very thin (.001"/25 micron) components - bellows, electroforms, diaphragms, membranes, etc.