다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Publisher Summary This chapter describes the mixed mode cracking in layered materials. There is ample experimental evidence that cracks in brittle, isotropic, homogeneous materials propagate such that pure mode I conditions are maintained at the crack tip. An unloaded crack subsequently subject to a combination of modes I and II will initiate growth by kinking in such a direction that the advancing tip is in mode I. The chapter also elaborates some of the basic results on the characterization of crack tip fields and on the specification of interface toughness. The competition between crack advance within the interface and kinking out of the interface depends on the relative toughness of the interface to that of the adjoining material. The interface stress intensity factors play precisely the same role as their counterparts in elastic fracture mechanics for homogeneous, isotropic solids. When an interface between a bimaterial system is actually a very thin layer of a third phase, the details of the cracking morphology in the thin interface layer can also play a role in determining the mixed mode toughness. The elasticity solutions for cracks in multilayers are also elaborated.

Mixed mode cracking in layered materials

http://www.tara.tcd.ie/bitstream/handle/2262/54960/Biomaterials%20and%20scaffolds%20for%20tissue%20engineering.pdf;sequence=1

Biomaterials & scaffolds for tissue engineering

Particle reinforced metal matrix composites are now being produced commerically, and in this paper the current status of these materials is reviewed. The different types of reinforcement being used, together with the alternative processing methods, are discussed. Depending on the initial processing method, different factors have to be taken into consideration to produce a high quality billet. With powder metallurgy processing, the composition of the matrix and the type of reinforcement are independent of one another. However, in molten metal processing they are intimately linked in terms of the different reactivities which occur between reinforcement and matrix in the molten state. The factors controlling the distribution of reinforcement are also dependent on the initial processing method. Secondary fabrication methods, such as extrusion and rolling, are essential in processing composites produced by powder metallurgy, since they are required to consolidate the composite fully. Other methods, suc...

Particle reinforced aluminium and magnesium matrix composites

This paper reviews the past, present, and future of the hydroxyapatite (HAp)-based biomaterials from the point of view of preparation of hard tissue replacement implants. Properties of the hard tissues are also described. The mechanical reliability of the pure HAp ceramics is low, therefore it cannot be used as artificial teeth or bones. For these reasons, various HAp-based composites have been fabricated, but only the HAp-coated titanium alloys have found wide application. Among the others, the microstructurally controlled HAp ceramics such as fibers/whiskers-reinforced HAp, fibrous HAp-reinforced polymers, or biomimetically fabricated HAp/collagen composites seem to be the most suitable ceramic materials for the future hard tissue replacement implants.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0884291400042527

Processing and properties of hydroxyapatite-based biomaterials for use as hard tissue replacement implants

Influence of the sodium content on the state, the dispersion, and the repartition of nickel oxide supported on .gamma.-alumina

Thermal stresses and thermal expansion in MMCs

Measurements have been performed on phosphorous‐implanted polysilicon films and TEM investigation has given indications about the mean grain size and about its dependence on the temperature and duration of annealing. Results have also been obtained concerning the sheet resistivity of the films. A semiquantitative model has been derived which attempts to explain the variation in sheet resistivity as a function of the doping level. The observation of both grain size and sheet resistivity suggests that not only segregation to grain boundary and grain growth occur during annealing but that a third phenomenon (a crystallographic relaxation at grain boundary) should occur at a temperature of about 1000°C.

Francis Delannay

Papers

Influence of the sodium content on the state, the dispersion, and the repartition of nickel oxide supported on .gamma.-alumina

Thermal stresses and thermal expansion in MMCs

Grain-size and Resistivity of Lpcvd Polycrystalline Silicon Films

On the precision of the wedge-opened double cantilever beam method for measuring the debonding toughness of adhesively bonded plates

Assessment of solid state and liquid phase sintering models by comparison of isothermal densification kinetics in W and W-Cu systems