1113 Strain Measurements by Laser Speckle Method and Evaluation of Mechanical Properties of Metallic Microelement

Abstract

To evaluate the mechanical properties of stainless steel film 17-7PH, tensile and tension-tension fatigue tests were conducted in laboratory air. The strain measurement system by laser speckle pattern was developed to measure the strain of the specimen under non-contact condition. Fracture surface was observed by scanning electron microscopy (SEM). The tensile strength and elongation to failure of the transverse specimens were larger than those of the longitudinal ones. However, no influence of specimen orientation on fatigue strength was observed. There observed some inclusions on the fracture surface of the specimens, and fatigue crack initiated from those inclusions.