polished copper test coupon specimen for ASTM D5968

ASTM D5968 Metal Test Specimens

Copper, lead, tin, and phosphor bronze test specimens used in ASTM D5968 (Corrosiveness of Diesel Engine Oil at 121°C). Each test specimen is 1" x 1" x 0.032" (2.5cm x 2.5cm x 0.081cm), with two dril