Question

Which of the following expression is used to calculate MPY?

(a) MPY=(543*W)/DAT

(b) MPY=(534*W)/DAT

(c) MPY=W/DAT

(d) MPY=DAT/(534*W)

I got this question by my school principal while I was bunking the class.

I'm obligated to ask this question of Corrosion Rate Expression in chapter Corrosion Principles of Corrosion Engineering

Answer 1

The correct choice is (b) MPY=(534*W)/DAT

To explain I would say: W = weight loss in milligrams, D=Density of a specimen (g/cm^3), A=Area of specimen(sq.in), T=time of exposure in hours and 534 is a conversion factor. MPY means mils penetration per year I.e. milli inches penetration per year.