EVALUATION ON THE TENSION AND FATIGUE BEHAVIOR OF VARIOUS PVD COATED MATERIALS

An axial tension-compression testing machine was used to compare the t ension and fatigue performance of the specimens with and without coati ngs grown by physical vapor deposition process. The surface morphology of the coating layers was examined utilizing a scanning electron micr oscope and an optical microscope. It was found that the application of surface films did not affect the Young's modulus and yield points but did little decrease the fracture strain. For fatigue, the application of the surface coatings improved the endurance limit by 20-40 MPa. (C ) 1998 Elsevier Science S.A. All rights reserved.