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Hydrogen brazing

Benefits Application & materials Process details

Hydrogen brazing is a braze process that uses the cleaning (reducing) properties of high purity hydrogen to improve the flow characteristics of the braze alloy. The hydrogen atmosphere reduces surface oxides on the parent material, enabling the braze alloy to flow (wet) more effectively to create a high integrity braze joint.

Benefits

  • Cleanliness – the reduction of surface oxides on the parent material improves the cleanliness and integrity of the braze joint.
  • Increased braze alloy and parent material options – enables the use of high vapour pressure braze alloys and parent materials that cannot be brazed within a vacuum atmosphere.

Application & materials

  • Medical devices
  • Electronic devices
  • Aerospace parts (precision machined stainless steel components)
  • High vapour pressure braze alloys (Cu, Ag, etc.)
  • High cleanliness assemblies

Hydrogen brazing can be applied to a multitude of materials such as stainless steel, copper and some nickel based alloys. Titanium alloys cannot be brazed in a hydrogen atmosphere. Hydrogen brazing reduces surface oxides at the faying surfaces, resulting in a clean, high integrity braze joint that improves the service characteristics of the finished part.

Process details

Hydrogen brazing can be performed within a sealed retort furnace or a hump back belt furnace. Both furnace types surround the part being processed within a high purity hydrogen atmosphere (typically with a dew point of less than minus 60°F). As the furnace load is heated above the liquidus temperature of the braze alloy, the hydrogen atmosphere reduces surface oxides present of the parent material and improves the wetting characteristics of the braze alloy.