Hydrogen and pressure sensors ? What should be observed?

When pressure gauge 10 bar come into contact with hydrogen, this often results in difficulties. Unfortunately, I very often notice in my own job our customers are not aware of this ahead of use. Because of this , they often do not even reveal that their medium contains hydrogen. We only learn when we get a complaint. But why do we get a complaint? How come especially hydrogen so critical to pressure sensors?
A simple rule is that numerous metals become brittle when exposed to hydrogen. Hydrogen atoms that diffuse into the metal grid change the strength of the material. In the worst case, this results in cracks in the material. Or even to put it simply, the pressure sensor starts leaking or is completely destroyed. In the case of pressure sensors, specifically thin membranes required for measuring pressure play a decisive role. เกจวัดแรงดัน will not only penetrate the metal, but additionally go through it by diffusion.
This has several effects: When piezoresistive measuring principles are used, it becomes critical if hydrogen reacts with the internal transmission medium or accumulates there. This initially only falsifies the measurement results, but can later on also lead to complete destruction of the sensor in individual cases. The addition of hydrogen also changes the instrumentation characteristics of the resistance structures of the measurement bridge of thin-film sensors. Despite being reversible, this process results in a detuning of the bridge at least temporarily, resulting in a falsification of the measurement signal.
However, the consequences described above occur in various materials differently. Which means that the consequences of hydrogen can be lowered substantially by selecting suitable materials.
Note
More info on our pressure sensors and about hydrogen are available on the WIKA website. If you use hydrogen as the medium, your contact will gladly recommend an optimum solution for your application.

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