Linear polarization resistance: a technique that nudges a probe electrode's potential by about 10 to 20 mV and measures the resulting current. The ratio gives polarization resistance, which is inversely proportional to corrosion rate through the Stern-Geary relationship. LPR responds within minutes, ideal for tuning inhibitor dosing in water systems, but it needs a continuous conductive liquid and does not see pitting directly.
LPR dropped from 8 mpy to under 1 within an hour of starting the inhibitor, that dose looks right.
Also heard as
- linear polarization resistance
- LPR probe
Related terms
ER probe
Electrical resistance probe that tracks corrosion by measuring the rising resistance of a thinning metal element.
Corrosion coupon
Weighed metal strip exposed inside a system for a set time, then reweighed to calculate corrosion rate.
Corrosion inhibitor
Chemical added in small doses to a fluid to slow corrosion of the metal it touches.
Polarization
Shift of a metal's potential away from its native value caused by current flowing across its surface.