Gas-driven hydrogen permeation at high temperature
The Hydrogen Diffusion Cell measures gas-driven permeation of hydrogen (H₂) and deuterium (D₂) through a disc sample. Gas is applied to one face of the sample. Gas that permeates through is carried from the other face to a high-vacuum measurement line. The compact cell sits inside a laboratory tube furnace, within the uniform-temperature zone. It is used to study hydrogen transport in metals and to evaluate permeation barrier coatings.
- Disc samples 1″ (25 mm) diameter, about 0.04″ (1 mm) thick
- Nickel-alloy C-ring seals for high-temperature service, or copper seals
- Fits inside a tube furnace, with single-ended 1/8″ (3 mm) gas connections
- Loose centering rings for easy assembly and inspection
- All components, including the seals, designed for reuse
- Complete gas-handling and pumping system available
Cross-section. The outlines show the furnace tube and its uniform-temperature zone.
Sealed for High Temperature
The sample is clamped between two cell caps with a metal seal on each face. Nickel-alloy C-rings are used for sustained high-temperature work. Custom Copper seals are a lower-cost choice up to about 450 °C. The cell caps have a knife edge for copper seals, and the nickel-alloy rings clear it, so a cell can be upgraded from copper to nickel-alloy seals later.
Built for the Tube Furnace
Both 1/8″ (3 mm) stainless steel gas tubes leave the same end of the cell, with one looped back, so the cell slides into the furnace from one side. The tubes pass out of the vacuum through a single flange with compression fittings, such as our Swagelok 133 Inline Passthru. With the furnace tube under vacuum, the sample edges are protected from oxidation, and any gas that bypasses the seals is pumped away.
Easy Sample Changes
Two loose centering rings keep the sample and seals aligned during assembly, and the stack can be inspected without taking the cell apart.
Exploded view
Complete System
The cell can be supplied alone, or with the gas-handling and pumping system around it. That system includes the gas supply and charging gauge, manual valves, turbomolecular and roughing pumps, ion gauge or RGA, and low-outgassing tubing.
Options
Seals: Nickel-alloy C-rings for high-temperature service, or copper seals up to about 450 °C.
Sample coupons: Stainless steel disc coupons, plain or prepared with a knife edge for copper seals.
Vacuum pass-through: Flange with 1/8″ (3 mm) compression-fitting pass-throughs for the gas tubes. See the Swagelok 133 Inline Passthru.
Gas handling and pumping: Valves, gauges, turbomolecular and roughing pumps, and 1/4″ (6 mm) stainless tubing and fittings, supplied or recommended.
Custom configurations: Other sample diameters and thicknesses, seal materials, tube sizes, and cell sizes to fit other furnaces.
CONTACT FACTORY FOR CUSTOMIZATIONS AND ADDITIONAL OPTIONS
Tech Specs
- Gases: hydrogen (H₂) and deuterium (D₂)
- Sample: disc, 1″ (25 mm) diameter, about 0.04″ (1 mm) thick standard; other sizes to order
- Seals: nickel-alloy C-rings, or copper up to about 450 °C
- Downstream side: high vacuum
- Gas connections: 1/8″ (3 mm) stainless steel tube, single-ended
- System tubing: 1/4″ (6 mm) stainless steel, compression fittings
- Heating: external tube furnace; cell sized to the furnace tube