ALSPEK H probe

ALSPEK H measures hydrogen using a solid electrolyte based concentration cell. The solid state proton conductor indium doped calcium zirconate is used as the electrolyte, in conjunction with a patented solid state hydrogen reference electrode. This internal hydrogen reference results in a completely self-contained sensor, requiring no external gas supply.

At the end of the probe there is a porous diffusion barrier. Hydrogen dissolved in the melt comes out of solution and enters a sealed gas cavity. The measuring electrode of a hydrogen concentration cell is exposed to the gas cavity, and the partial pressure of hydrogen inside the cavity is calculated from the cell voltage. This is then used, in conjunction with hydrogen solubility data, to calculate the quantity of hydrogen dissolved in the melt.

Hydrogen solubility depends upon melt chemistry. The ALSPEK H analyser provides 7 pre-set alloy settings and one custom setting, allowing easy calibration for different alloys.





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