Hydrogen and pressure sensors ? What must be observed?

When pressure sensors come into contact with hydrogen, this often results in difficulties. Unfortunately, เกจวัดแรงดัน notice in my own job our customers have no idea of this ahead of use. This is exactly why they often usually do not even tell us that their medium contains hydrogen. We only find out when we get a complaint. But why do we get a complaint? Why is 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. Atomic hydrogen will not only penetrate the metal, but additionally pass through it by diffusion.
It has several effects: When piezoresistive measuring principles are employed, it becomes critical if hydrogen reacts with the inner 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 technique results in a detuning of the bridge at the very least temporarily, resulting in a falsification of the measurement signal.
However, the consequences described above occur in various materials differently. Because of this the effects of hydrogen could be lowered substantially by selecting suitable materials.
Note
More info on our pressure sensors and about hydrogen can be found on the WIKA website. If you are using hydrogen because the medium, your contact will gladly recommend an optimum solution for your application.