Nondestructive evaluation of the prevailing compressive residual stress in the shallow subsurface layer of surface-treated metals is greatly complicated by the accompanying surface roughness and cold work. A high-precision laser-ultrasonic technique has been developed to study the feasibility of SAW dispersion spectroscopy for residual stress assessment on surface-treated metals in a wide frequ...

In light of its frequency-dependent penetration depth, the measurement of eddy current conductivity has been suggested as a possible means to allow the nondestructive evaluation of subsurface residual stresses in shot-peened specimens. This technique is based on the socalled electro-elastic effect, i.e. the stress-dependence of the electrical conductivity. Unfortunately, the relatively small ch...

The compressive stress distribution below the specimen surface of severely surface deformed steels by shot peening was investigated by using laboratory X-rays and high-energy X-rays from a synchrotron radiation source, SPring-8 in the Japan Synchrotron Radiation Research Institute. Medium carbon steel plates were heat treated in two different conditions. The Vickers hardness of material-A and B...

Because of their frequency-dependent penetration depth, eddy current measurements are capable of mapping the near-surface depth profile of the electrical conductivity. This technique is used to nondestructively characterize the subsurface residual stress and cold work distributions in shot-peened metal components. Unfortunately, the spurious surface roughness produced by the shot peening proces...

Ultrasonic peening treatment (UPT) as a method of severe plastic deformation was used to treat cruciform welded joints of Q345 steel. The application of UPT achieves material surface nanocrystallization of the peening zone, reduces stress concentration, and produces residual compressive stresses at the welded toe. Micro-structure, hardness, stress relief, S-N curve, and the fatigue fracture mec...

The as-built selective laser melted (SLM) austenitic stainless steel 316 L components are characterized by presence of quality related concerns such as tensile residual stresses, poor surface finish, etc. These issues may prove to be detrimental during the actual usage and could result in mechanical performance. Therefore, it is important perform apt post processing heat treatment shot peening ...

This work presents a non-destructive method for quantitative essessment of fatigue damage materials with linear elastic properties using nonlinear ultrasonic techniques. A study was conducted on these and shot peening processing technique. numerical based the semi-analytical finite element (SAFE) technique, used to obtain phase-matching modes specimens. Experiments confirm that nonlinearity sam...