Numerical Model of Bond Strength Measurements

1989 ◽  
Vol 159 ◽  
Author(s):  
Gerald L. Nutt

ABSTRACTWe have reported bond strength measurements of metal/ceramic interfaces using shock waves to separate the bond by spallation[1,2]. The technique relies on the interpretation of the free surface velocity of the metal film as it is spalled from the substrate.We answer several questions relating to the details of the interaction of the shock with the interface. Specifically, we examine the role of sound speeds in the measurements. We also calculate the plastic strain in the the bond region and verify the theory relating to the jumpoff velocity of the scab to the bond strength.

1989 ◽  
Vol 153 ◽  
Author(s):  
Gerald L. Nutt ◽  
William Lai ◽  
Kenneth E. Froeschner ◽  
Wayne E. King

AbstractWe report on a novel method for measuring the bond strength of metal/ceramic interfaces. Test specimens are created by vapor depositing a metal film on a ceramic substrate. The specimen is impacted with a thin metal flyer sending a short planar shock pulse into the ceramic. If the shape and amplitude of the wave is properly controlled the interface will spontaneously debond creating new free surfaces.Measurements indicate the debonding process occurs in less than 1.0 ns, which we believe is too short for crack propagation along existing flaws. Therefore, we conclude that simultanious breaking of atomic bonds rather than propagation and coalescence of cracks is the means by which the film and substrate are separated. The free surface velocity of the metal overlayer is monitored during spall by laser interferometry. The data constitute a direct measurement of the bond strength. The measured bond strengths are reproducible and do not show a dependence on shock amplitude for identically prepared specimens.


2019 ◽  
Vol 263 ◽  
pp. 15-23 ◽  
Author(s):  
Abdulrahman Al-Behadili ◽  
Mathieu Sellier ◽  
James N. Hewett ◽  
Roger I. Nokes ◽  
Miguel Moyers-Gonzalez

2019 ◽  
Vol 140 ◽  
pp. 117-122 ◽  
Author(s):  
Kohei Hamaguchi ◽  
Eiji Hoashi ◽  
Takafumi Okita ◽  
Kenzo Ibano ◽  
Yoshio Ueda

2015 ◽  
Vol 64 (3) ◽  
pp. 034601
Author(s):  
Pei Xiao-Yang ◽  
Peng Hui ◽  
He Hong-Liang ◽  
Li Ping

1970 ◽  
Vol 96 (7) ◽  
pp. 1485-1502
Author(s):  
Gordon H. Flammer ◽  
J. Paul Tullis ◽  
Earl S. Mason

2006 ◽  
Author(s):  
Jiangang Zhao ◽  
Roger E. Khayat

The similarity solutions are presented for the wall flow which is formed when a smooth planar jet of power-law fluids impinges vertically on to a horizontal plate, and spreads out in a thin layer bounded by a hydraulic jump. This problem is formulated analogous to radial jet flow problem and the solution procedure is accounted for by means of similarity solution of the boundary-layer equation [1] for Newtonian fluids. For the convenience of analysis, the flow may be divided into three regions, namely a developing boundary-layer region, a fully viscous boundary-layer region, and a hydraulic jump region. The similarity solutions of the film thickness and free surface velocity in fully viscous boundary-layer region include unknown constant L, which is solved numerically and approximately in the developing boundary-layer flow region. Comparison between the numerical and approximate solutions leads generally to good agreement, except for severely shear-thinning fluids. The boundary-layer solution depends on two parameters: power-law index n and α, the dimensionless flow parameters. The effect of α on film thickness and free surface velocity is investigated. The relations between the position of the hydraulic jump and dimensionless flow parameter are obtained and the effect of α on the position of the jump is presented.


1981 ◽  
Vol 36 (5) ◽  
pp. 437-442
Author(s):  
K. Hollenberg ◽  
H.-R. Kleinhanß ◽  
G. Reiling

Abstract The Chapman Jouguet pressure of some high explosives is measured by X-ray absorption giving the density behind the detonation front. An accuracy of 2 - 3% was achieved in the pressure range of 200 kbar. The pressures are considerably lower than comparable results of other authors obtained by the free surface velocity method or similar techniques.


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