Q:
What is the procedure for a
Corrosion or Oxidation Test?





A:

    CORROSION TEST:

  • Expose a weighed coupon to the corrodent for a
    known time, remove, clean to remove the corrosion
    products and reweigh.

  • Corrosion rate R is:
    R = K W/Atd

  • K is a constant (3.45 X 10 to the power of 6
    for rate in mils of thickness loss per year.
    )

  • W is weight loss in grams (to 0.001 grams)

  • A is area exposed (to 0.01 square cm)

  • t is exposure time in hours (to 0.01 hr)

  • d is the density in grams per cubic cm


    OXIDATION TEST:

  • If atmosphere or environmental at or near ambient
    temperature, same test as corrosion.

  • At elevated temperature, test is done in a
    thermogravimetric analysis (TGA) set up.

    - Temperature is controlled by a furnace.

    - A controlled atmosphere surrounds a specimen coupon
       on a very precise balance.

    - Weight change is measured continuously and
       is plotted versus time.