Recent developments in the laser spallation technique to measure the interface strength and its relationship to interface toughness with applications to metal/ceramic, ceramic/ceramic and ceramic/polymer interfaces

1994 ◽  
Vol 8 (6) ◽  
pp. 713-747 ◽  
Author(s):  
Vijay Gupta ◽  
Jun Yuan ◽  
Alexander Pronin
1998 ◽  
Vol 13 (10) ◽  
pp. 2881-2887 ◽  
Author(s):  
J. D. Kiely ◽  
D. A. Bonnell

Based on observations of plasticity on fracture surfaces, we propose two fracture mechanism for Ni-sapphire interfaces. A brittle-type mechanism is proposed for the decohesion of Ni from sapphire by which cracks advance in increments of 20 nm. When particulates that increase the interface strength are present, debonding occurs at the leading edge of the particulate, and unsteady crack advance occurs. Additionally, toughening mechanisms are proposed for each type of plasticity feature observed, and the fracture energy of each mechanism is quantified. Comparison of energy dissipated by these mechanisms with measured fracture energies indicates how the fracture energy of the interface varies with sulfur segregation and environmental embrittlement.


2018 ◽  
Vol 876 ◽  
pp. 25-30
Author(s):  
Liliana Porojan ◽  
Mihaela Bîrdeanu ◽  
Cristina Savencu ◽  
Sorin Porojan

It is known that the quality of metal-ceramic restorations mainly depends on the interface strength. The aim of the study was to evaluate metal–ceramic interfaces of heat pressed ceramic on Co-Cr frameworks obtained with different technologies: melting-casting (CST), computerized milling (MIL), selective laser sintering (SLS) and selective laser melting (SLM). The microstructure of metal–ceramic interfaces and framework topography were characterized by scanning electron microscope (SEM). Sandblasted, polished surfaces and the cross section on the interfaces were observed. Sandblasted surfaces presented a uniform rough aspect and pronounced porous surface compared to that of polished surfaces and were better visible in SLS and SLM samples. The thickness of the veneer layer had a noticeable effect on the interface, because in the case of thicker veneers, cracks at the interfaces were visible for CST and MIL specimens. Considering the findings reported herein, some suggestions can be considered in practice, such as adaptation of the restorations morphology to the characteristics of the processed materials.


Vacuum ◽  
2004 ◽  
Vol 73 (3-4) ◽  
pp. 533-539 ◽  
Author(s):  
Akira Kobayashi ◽  
Amit Jain ◽  
Vijay Gupta ◽  
V. Kireev

2015 ◽  
Vol 2015 (0) ◽  
pp. _OS1205-38-_OS1205-38
Author(s):  
Masahiro ARAI ◽  
Masaomi NISHIMURA ◽  
Saisuke SUGIURA ◽  
Hiroaki ITO ◽  
Hideo CHO

1992 ◽  
Vol 40 (1) ◽  
pp. 141-180 ◽  
Author(s):  
V. Gupta ◽  
A.S. Argon ◽  
D.M. Parks ◽  
J.A. Cornie

1995 ◽  
Vol 409 ◽  
Author(s):  
Yueguang Wei ◽  
John W. Hutchinson

AbstractA mechanics study of the interface toughness of joints comprised of ceramic substrates joined by a thin ductile metal layer is carried out for arbitrary combinations of mode I and mode II loading. The crack lies on one of the metal/ceramic interfaces, and the mechanism of separation at the crack tip is assumed to be atomic decohesion. The SSV model proposed by Suo, Shih and Varias is invoked. This model employs a very narrow elastic strip imposed between the substrate and the ductile layer to model the expected higher hardness of material subject to high strain gradients and possible dislocation-free zone in the immediate vicinity of the crack tip. The criterion for crack advance is the requirement that energy release rate at the crack tip in this narrow elastic strip be the atomistic work of fracture. The contribution of plastic dissipation in the metal layer to the total work of fracture is computed as a function of the thickness and yield strength of the layer and of the relative amount of mode II to mode I. Ductile joints display exceptionally strong thickness and mixed mode dependencies.


2019 ◽  
Vol 21 (21) ◽  
pp. 11266-11283 ◽  
Author(s):  
Jeeno Jose ◽  
Narasimhan Swaminathan

Chemical crosslinks significantly contribute to the interface strength, and help to better preserve the strength even after multiple mechanical loading cycles.


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