Ultrasonic Nondestructive Evaluation Systems
Models and Measurements
Page
%P
60 Result(s)
within
Xu** Song
Engineering
Characterization and Evaluation of Materials
Vibration, Dynamical Systems, Control
-
Article
Ultrasonic flaw classification in weldments using probabilistic neural networks
A probabilistic neural network is used here to classify flaws in weldments from their ultrasonic scattering signatures. It is shown that such a network is both simple to construct and fast to train. Probabilis...
-
Article
Fatigue crack initaition and propagation from hole defects
The aim of this study is to investigate the interaction of two hole defects affecting fatigue crack initiation life and propagation behavior. The location of two hole defects was characterized by an angle of a...
-
Article
Effect of plastic zone on the fatigue crack propagation behavior between two fatigue cracks
In this study, the fatigue crack propagation behavior in the stress interaction field between two different fatigue cracks is studied by experiment and finite element analysis. In the experiment, the offset di...
-
Article
Dynamic small strain measurements of a metal specimen with a split Hopkinson pressure bar
When a conventional split Hopkinson pressure bar (SHPB) is used to investigate the dynamic flow behavior of ductile metals, the results at small strains (ɛ≲2%) are not considered valid owing to fluctuations as...
-
Article
Modeling Ultrasonic Pulse-Echo Signals from a Flat-Bottom Hole in Immersion Testing Using a Multi-Gaussian Beam
This paper proposes an ultrasonic measurement model that can predict the pulse-echo signals from a flat-bottom hole in an isotropic, homogeneous solid specimen immersed in water in a computationally efficient ...
-
Article
Dynamic stress equilibration in split Hopkinson pressure bar tests on soft materials
The condition of dynamic stress equilibrium is not satisfied automatically when a split Hopkinson pressure bar (SHPB) is employed to determine the dynamic properties of soft materials. In order to develop guid...
-
Article
Modeling Angle Beam Ultrasonic Testing Using Multi-Gaussian Beams
This paper proposes a new approach to modeling angle beam ultrasonic testing that can predict pulse-echo signals, in an absolute and computationally efficient manner, from various reflectors in steel welded jo...
-
Article
Loading and unloading split hopkinson pressure bar pulse-sha** techniques for dynamic hysteretic loops
Pulse-sha** techniques are developed for both the loading and unloading paths of a split Hopkinson pressure bar (SHPB) experiment to obtain valid dynamic stress-strain loops for engineering materials. Front ...
-
Article
Upper limit of constant strain rates in a split Hopkinson pressure bar experiment with elastic specimens
The upper limit of the achievable constant strain rates in linearly elastic specimens loaded by a split Hopkinson pressure bar is estimated based on the specimen properties and a linear ramp loading. The crite...
-
Article
Dynamic and Quasi-Static Propagation of Compaction Waves in a Low-Density Epoxy Foam
We conducted dynamic and quasi-static compression experiments with low-density (ρ = 120 kg/m3) epoxy foam specimens. The specimens had a 10.0-mm-square cross-section and a length of 19.3 mm. Dynamic experiments w...
-
Article
Energy for Specimen Deformation in a Split Hopkinson Pressure Bar Experiment
-
Book
-
Article
Determination of Early Flow Stress for Ductile Specimens at High Strain Rates by Using a SHPB
In a dynamic experiment to obtain the high-rate stress–strain response of a ductile specimen, it takes a finite amount of time for the strain rate in the specimen to increase from zero to a desired level. The ...
-
Article
Radial Inertia Effects in Kolsky Bar Testing of Extra-soft Specimens
Impact responses of extra-soft materials, such as ballistic gelatins and biological tissues, are increasingly in demand. The Kolsky bar is a widely used device to characterize high-rate behavior of materials. ...
-
Article
A Long Split Hopkinson Pressure Bar (LSHPB) for Intermediate-rate Characterization of Soft Materials
In this study, we developed a long split Hopkinson pressure bar (LSHPB) for mechanically characterizing soft materials at intermediate strain rates. Using a proper pulse shaper, a loading pulse over 3 ms was p...
-
Article
Dynamic Tensile Testing of Soft Materials
Determination of dynamic tensile response of soft materials has been a challenge because of experimental difficulties. Split Hopkinson tension bar (SHTB) is a commonly used device for the characterization of h...
-
Chapter
Dynamic Characterization of Soft Materials
Soft materials, such as elastomers, foams, gels, and biological tissues, possess low stiffness, yield strength, and wave speeds. These characteristics pose challenges in experiment design to obtain the dynamic...
-
Article
High-rate Characterization of 304L Stainless Steel at Elevated Temperatures for Recrystallization Investigation
An integrated experimental technique was developed for high-rate mechanical characterization of 304L stainless steel at elevated temperatures by using a modified split Hopkinson pressure bar (SHPB). A sandwich...
-
Article
Wrinkle-Based Measurement of Elastic Modulus of Nano-Scale Thin Pt Film Deposited on Polymeric Substrate: Verification and Uncertainty Analysis
Wrinkle-based measurement of elastic modulus for a nano-scale thin film was analyzed. As a demonstrative example, the wrinkles of Pt films on a Polydimethylsiloxane (PDMS) substrate under compressive loading w...
-
Article
Boundary Integral Equation for Eddy-Current Problems with Dirichlet Boundary Condition
A boundary integral equation (BIE) is developed for the eddy-current (EC) problems with Dirichlet boundary condition by considering the difference between the field without cracks and the one with cracks. Once...
