Ceramics brittle nature

Additionally, the packing media need to be able to withstand thermal shock or fatigue due to, for example, reactor start-up and shut-down cycles, and, in those cases involving ceramic membranes, absorb mechanical shock from the operation of the unit. Due to their relatively brittle nature, for example, commercial ceramic membranes currently often use some flexible materials, such as polymers, for the connectors to adsorb mechanical vibration. 

The brittle nature of ceramics together with the stochastic nature of finding flaws of different sizes, shapes, and orientations relative to the applied stress will invariably result in some scatter to their strength. According to the Weibull distribution, the survival probability is given by... 

P.F. Becher, S.L. Hwang, C.H. Hsueh, Using microstructure to attack the brittle nature of sUicon nitride ceramics, MRS Bulletin 10 [2] 23-27 (1995)... 

Ceramics for Bone Applications. Since bone is a composite consisting essentially of ceramic and polymeric components, and due to the essential inertness of many ceramics, this class of materials was looked to to find truly biocompatible materials for structural applications. However, the brittle nature and low tensile strength of ceramics have led to some concerns regarding the fracture behavior... 

Main risks to the success of all forms of CWF are hairline cracks and cross-contamination. If the imit is dropped or otherwise abused, the brittle nature of ceramic materials can allow fine, hard to see hairline cracks, and pass contaminants through the filter. 

Because of the brittle nature of ceramics, special instrumented Charpy Impact Test (henceforth CIT) machines were developed, primarily to evaluate the... 

Developing appropriate ceramic—matrix composites [henceforth CMCs] for possible aero-engine applications started more than a decade ago. CMCs continue to be developed for improved toughness, to overcome the inherently brittle nature of most of the monolithic ceramics. Many experiments have shown that long-term loading of CMCs (for thousands of hours) produce improved high-temperature properties in monolithic ceramics by causing the dispersion of ceramic whiskers or... 

The satisfactory sealing of Na/S cells is another difficult technical problem It is necessary to provide three separate seals - to seal both the sodium and the sulphur electrodes from the atmosphere and also from each other In addition to being leak-tight, these seals must be chemically and electrochemically compatible with the reactants they contain (sodium and S/Na S, respectively) at temperatures up to 400 C and for periods of several years Ideally, the seals will have some flexibility to compensate for the rigidity and brittle nature of the ceramic tube ... 

Adhesion is becoming more and more important in many situations in dentistry. Effective adhesion retains restorative dental materials at proper positions of tooth structure, solves the problem of leakage around restorations, and, consequently, improves their performances. Recently, adhesion of ceramic restorative materials is attracting increasingly more attention, as ceramics are highly desirable for esthetic restoration in terms of toothlike appearance, inertness, and durability. Because of their brittle nature, however, the ceramics must be bonded steadily to tooth structure to assure endurance under continual occlusal load for practical uses as dental materials. 

In the field of engineering ceramics, ceramic composites have been increasingly studied for overcoming brittle nature of monolithic ceramics. Ceramic composites... 

Elevated temperature applications require materials that can maintain good mechanical properties such as strength and hardness. Ceramics have good mechanical properties at high temperature and, thus, appear to be good candidates for elevated temperature applications. However, due to their brittle nature, monolithic ceramics are unsuitable for many applications where reliability is a critical issue. In the last few years, a new class of ceramic materials has been developed and studied. It is understood that two brittle materials can show non-brittle behavior if they are properly mixed. Fiber-reinforced ceramic matrix composites (CMCs) exhibit pseudo-plastic behavior at room temperature, as well as in an elevated temperature environment. Since the fiber and the matrix are made of ceramic material, creep behavior and hazardous emissions are reduced considerably. 

Prior to the Bronze Age, human tools and vessels were primarily made of stone (a ceramic). Between 3000 and 4000 years ago, metals came into widespread use because of their toughness that is derived from their ductility. For most of that history, ceramic materials were somewhat limited in applicability because of their brittle nature. Their principal drawback has been a disposition to catastrophic fracture in a brittle manner with very little energy absorption. Although many new composites and other... 

Porous ceramics are widely used in various versatile applications, such as liquid gas filters, catalysis supports, gas distributors, insulators, preforms for metal-impregnated ceramic metal composites, and implantable bone scaffolds [1, 2]. Unlike in metallic or pol)rmeric products, pores have been traditionally avoided in ceramic components because of their inherently brittle nature [3,4]. However, porous ceramics have become increasingly essential, especially for use in environments involving high temperatures, extensive wear and corrosive media [5,... 

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