Background
Being composed of a single proton and an electron, hydrogen is the lightest and most abundant chemical element in the universe. Its molecular size and high mobility allows it to exist nearly everywhere, in many forms, often without detection.
The accumulation of hydrogen in certain materials can lead to sudden and catastrophic failure through embrittlement, posing a threat to both personnel and critical infrastructure if left unchecked. The mechanical behaviour of metals can be significantly affected by even minor exposure to hydrogen, which is often challenging to address in initial engineering designs, and the maintenance regimes used in today’s transportation and energy sectors.
The need for robust hydrogen-compatible designs is now more evident than ever before with the rapidly emerging hydrogen economy, in which this future fuel is expected to significantly change the industrial, commercial, and residential sectors over the next few decades. A high-sensitivity measurement method for hydrogen in metals will become strategically important for the general adoption of hydrogen-based technologies.
Preliminary Research
Technical Information
Solutions
Our mission is to combat material corrosion of in-service components and to aid the design of next-generation hydrogen-compatible materials by providing solutions for advanced hydrogen analytics.
Figure 1 - Overview of the hydrogen sensing apparatus.
Theory of Operation
A system has been developed to measure hydrogen gas extracted from pre-weighed metal samples through a thermal process (Figure 1). Samples may include scrapes collected from metal surfaces after removing an oxide or a solid metal sectioned from a part. When sufficient heat is applied to a metal sample, hydrogen within will become highly mobile interstitial atoms. Under anoxic conditions, the surface oxide that surrounds a base metal sample breaks down at high temperatures and no longer acts as a barrier to hydrogen. Thermal extraction of hydrogen for analysis is now possible under both vacuum and inert carrier gas conditions (Figure 3). Inert gases include helium and argon.
Figure 2 - Range and sensitivity comparison to existing mass spectrometry techniques.
Figure 3 - Typical thermal desorption example of a 138.66 mg zirconium alloy with 0.832 µg gaseous hydrogen gas equivalent to 12 µg/g.
Preliminary Specifications
Selectivity: specific to hydrogen isotopes
Tested Range: 0.25 nmol to 4.25 µmol of H2
Sample Size: 50 mg to 300 mg of material
Accuracy: typically, less than 5 %
Responsiveness: real-time
Furnace Range: up to 2000 °C at 5 °C/s
Unique Selling Points
Logistical Considerations
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Offers superior measurement sensitivity and sample processing turnaround time to existing techniques.
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Highly cost-competitive with differential scanning calorimetry (DSC) and other measurement techniques.
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Adopts a simple modular design concept, using high-reliability components for low operating and maintenance costs.
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The portable size and weight of the apparatus allow for onsite measurements and effortless transportation between test facilities.
Analytical Considerations
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Extensive measurement range from 0.005 µg/g to 200 µg/g in a 50 mg sample (Figure 2).
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Repeated results are feasible with a segmented sample due to superior sensitivity.
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SI traceable through the calibration of the equipment.
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There is no requirement to calibrate between measurements to achieve ideal conditions.
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The analysis process can be fully automated, with only minimal sample preparation required.
