Wave deformation

Influence of Shock-Wave Deformation on the Structure/Property Behavior of Materials... 

In this chapter, we will review the effects of shock-wave deform.ation on material response after the completion of the shock cycle. The techniques and design parameters necessary to implement successful shock-recovery experiments in metallic and brittle solids will be discussed. The influence of shock parameters, including peak pressure and pulse duration, loading-rate effects, and the Bauschinger effect (in some shock-loaded materials) on postshock structure/property material behavior will be detailed. 

Figure 6.1. Stress-strain behavior of shock-loaded copper compared to the annealed starting condition illustrating an enhanced flow stress following shock-wave deformation compared to quasi-static deformation (based on an equivalent strain basis).

The structure/property relationships in materials subjected to shock-wave deformation is physically very difficult to conduct and complex to interpret due to the dynamic nature of the shock process and the very short time of the test. Due to these imposed constraints, most real-time shock-process measurements are limited to studying the interactions of the transmitted waves arrival at the free surface. To augment these in situ wave-profile measurements, shock-recovery techniques were developed in the late 1950s to assess experimentally the residual effects of shock-wave compression on materials. The object of soft-recovery experiments is to examine the terminal structure/property relationships of a material that has been subjected to a known uniaxial shock history, then returned to an ambient pressure... 

P.S. Follansbee, High-Strain-Rate Deformation Mechanisms in Copper and Implications for Behavior during Shock-Wave Deformation, in Shock Waves in Con-... 

M.A. Meyers and L.E. Murr, Defect Generation in Shock-Wave Deformation, in Shock Waves and High-Strain-Rate Phenomena in Metals (edited by M.A. Meyers and L.E. Murr), Plenum, New York, 1981, 487 pp. 

B.L. Holian. Modeling shock-wave deformation via molecular-dynamics. Phys. Rev. A, 37(7) 2562—2568, 1988. 

Permanent strain Not required a. Total b. Effective a. Seismic b. Wave Deformation Lee (1974) Wright (1976) Chaney (1979,1980)... 

Fig. 1.9. Capillary waves deformation of a surface at a given instant for a wave of wave vector q...

Nowadays, many researchers are developing various numerical models of random wave transformations. They have to adopt some kind of wave-breaking criteria and energy dissipation mechanism so that the model can reproduce wave deformation in the nearshore waters. However, modelers seem to pick up whatever is readily available without deliberation on the physical features of the wave-breaking process and the appropriateness of the breaking model. 

Y. Goda, Irregular wave deformation in the surf zone, Coastal Eng. Jpn, JSCE 18, 13-26 (1975). 

R. L. Street and F. E. Camfield, Observations and experiments of solitary wave deformation, Proc. 10th Conf. Coast. Eng., Tokyo, Japan (1966), pp. 284-301. 

The frequency dependence of the propagation constant appears as a wave deformation in the time domain. This is measured as a voltage waveform at distance x when a step (or impulse) function voltage is applied to the sending end of a semi-infinite line. The voltage waveform. 

The reason for the much smaller wave deformation in the aerial modes than in the earth-return modes is that the conductor internal impedance that contributes mainly to the aerial modes is far smaller than the earth-return impedance that mainly contributes to mode 0. 

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