ASTM Standard C633-79, “Standard Test Method for Adhesion or Cohesive Strength of Flame-Sprayed Coatings,” is widely used in industry and research for evaluating bond strengths of thermal spray coatings. Tests are conducted by applying the coating to the end of a cylindrical test specimen 25.4 mm (1 in.) in diameter by 25.4 mm (1 in.) long. The coating surface is bonded to an uncoated cylinder of the same material and geometry. The force required to pull the cylinders apart is recorded. The bond strength is calculated by dividing the maximum force by the area of the 1 -in. diameter cylinder assuming that the stress is uniform over the area where the debonding occurs.