Non-contact Measurement of Elastic Modulus by using Laser Ultrasonic
http://link.springer.com/article/10.1007/s12541-015-0118-x
Non-contact measurement of elastic modulus by using laser ultrasound
Abstract
Non-contact measurement of elastic modulus is necessary for the in-line assessment of material in harsh environments such as high temperature. In this paper, a fully non-contact method to measure elastic modulus is proposed based on the laser ultrasonic technique (LUT) that uses a short-pulsed laser to generate ultrasound and the other laser coupled to an interferometer using a photorefractive crystal to detect the ultrasonic wave displacement. Basically, this method measures velocities of shear wave and longitudinal wave to obtain the elastic modulus. The uniqueness is that the velocity of shear wave is measured in the thermo-elastic regime first and then the velocity of longitudinal wave is measured in the ablation regime. This is because the strong mode of generated ultrasound is the shear wave in the thermo-elastic regime while the longitudinal wave in the ablation regime. Regime change can be achieved simply by switching the laser power, with no change in the measurement setup. In order to demonstrate the usefulness of the proposed method, the elastic modulus of aluminum casting alloy has been measured and the results were compared with a conventional contact method and a destructive tensile test. They showed good agreement with each other, which verified the usefulness of the proposed noncontact elastic modulus measurement method.
Keywords
Elastic modulus Laser ultrasound Non-contact Non-destructive-
Improvement of Crack Sizing Performance by using Nonlinear Ultrasonic Technique
-
Laser ultrasonic inspection in ablation regime
-
Influence of laser beam profiles on the frequency bandwidth of laser-generated surface acoustic waves
-
Real-time detection of surface cracks on silicon wafers during laser beam irradiation
-
Influence of repetitive pulsed laser irradiation on the surface characteristics of an aluminum alloy in the melting regime
-
Non-Contact Evaluation of Acoustic Nonlinearity of a Laser-Generated Surface Wave in a Plastically Deformed Aluminum Alloy
-
Relationship between Second- and Third-order Acoustic Nonlinear Parameters in Relative Measurement
-
Non-contact Measurement of Elastic Modulus by using Laser Ultrasonic
-
Relative Measurement of Acoustic Nonlinear Parameters and Comparison of Sensitivity to Thermal Aging
-
Demonstration of Disturbance Propagation and Amplification in Car-Following Situation for Enhancement of Vehicle Platoon System
-
Nanotribological and wetting performance of hierarchical patterns
-
Comparison of Ultrasonic Nonlinear Parameters Measured by PZT and LiNbO3 Transducers
-
Experimental Comparison of Nonlinear Parameters Obtained from Absolute Measurement and Relative Measurement
-
Absolute Measurement and Relative Measurement of Ultrasonic Nonlinear Parameter
-
Assessment of Thermal Aging of Aluminum Alloys by Acoustic Nonlinearity Measurement of Surface Acoustic Waves
-
Assessment of Thermal Degradation by Cumulative Variation of Ultrasonic Nonlinear Parameter
-
Finite element analysis of a low-velocity impact test for glass fiber-reinforced polypropylene composites considering mixed-mode interlaminar fracture toughness
-
A Method to Estimate the Absolute Ultrasonic Nonlinearity Parameter from Relative Measurements
-
Relative Measurement of the Acoustic Nonlinearity Parameter using Laser Detection of an Ultrasonic Wave
-
Dependence of Nonlinear Ultrasonic Characteristic on Second-Phase Precipitation in Heat-Treated Al 6061-T6 alloy