m/yr

meter per year

Corrosion rateexact by definition

The metre per year is the coherent base unit of this type: metal thickness lost per year of exposure, expressed as a uniform penetration rate. Its factor of 1 is exact. Real corrosion rates are far smaller than a metre a year, so this unit exists as the arithmetic base rather than as a working unit; mm/yr and mpy are what engineers actually use.

Watch out: A corrosion rate is a uniform-penetration figure. It says nothing about pitting, which can perforate a tube while the average metal loss stays negligible. A cooling loop reporting an excellent 1 mpy general rate can still fail from a single pit within a year.

1 m/yr 1,000 mm/yr
Solvers that use corrosion rate