MECHANICAL-PROPERTIES OF BORON COATINGS

Internal stress of coatings will cause reliability problems, such as a dhesion failure and peeling. We measured the internal stress in boron coatings, which was prepared by the ion plating method, with an appara tus based on the optically levered laser technique. The boron coatings exhibited large compressive stress in the range from -0.5 GPa to -2.6 GPa. It was found that these compressive stresses were decreasing fun ctions of the deposition rate and were increasing functions of the ion bombardment energy.