An experimental study of the rotary ultrasonic drilling of ceramics is first presented. The influence of different process parameters on the material removal rate for machining of magnesia stabilized zirconia is examined. Then a mechanistic approach to modeling the material removal rate during rotary ultrasonic drilling of ceramics is proposed and applied to predicting the material removal rate...

One of the obstacles to the industrial use of metal matrix composite materials is the damage they rapidly undergo when they are subjected to cyclic thermal loadings; local thermal stresses of high level can develop, sometimes nearby or over the elastic limit, due to the mismatch of elastic and thermal coefficients between the fibers and the matrix. For the same reasons, early cracks can appear ...

Hydroxyapatite Ca10(PO4)6(OH)2 (HAp) and calcium phosphate ceramic materials and coatings are widely used in medicine and dentistry because of their ability to enhance the tissue response to implant surfaces and promote bone ingrowth and osseoconduction processes. The deposition conditions have a great influence on the structure and biofunctionality of calcium phosphate coatings. Corrosion proc...

The dental practice is not only about prevention and treatment of oral diseases but also the fulfillment of demands of all who seek oral care, of which esthetics weighs more importance than any. To achieve excellence in the delivery of dental care, dentists rely on the vast array of modern advances in dental materials and restoration fabrication technologies. Need for more esthetical, metal-fre...

Currently, exchanging trends in the expensive usage of ceramic materials such as alumina, zirconia etc. into economical ceramic raw sources have been studied extensively over the last decade for various technological applications. Despite the fact that this ceramic compound or elements offer a great performance and stability, especially at high temperature and corrosive or acidic conditions, th...

the basic trait in the ceramics is their high brittle or low fracture toughness, and the main criteria in the design and application is specifying the fracture toughness in ceramics. in this paper, a new method is proposed to determine the fracture toughness of ceramics, which is enhanced in lowering the cost of fracture toughness determination relative to the previous methods. hence due to the...

High-strength all-ceramic materials are commonly used in dentistry. When complications occur in an all-ceramic restoration, the restoration is usually replaced. This article describes the time-saving ability and cost-effectiveness of this novel technique for the addition of a pontic in two complicated clinical cases. Turkom-Cera(™) [Turkom-Ceramic (M) Sdn. Bhd.] with aluminum oxide (99.98%) is ...

Preceramic polymers were proposed over 30 years ago as precursors for the fabrication of mainly Si-based advanced ceramics, generally denoted as polymer-derived ceramics (PDCs). The polymer to ceramic transformation process enabled significant technological breakthroughs in ceramic science and technology, such as the development of ceramic fibers, coatings, or ceramics stable at ultrahigh tempe...

OBJECTIVE The interest of dental research in metal-free restorations has been rising in the last 20 years following the introduction of innovative all-ceramic materials in the daily practice. In particular, high strength ceramics and related CAD/CAM techniques have widely increased the clinical indications of metal-free prostheses, showing more favourable mechanical characteristics compared to ...

This paper deals with the damage of ceramic materials after impact. The main information on the phenomenology and the kinetic damage are often localized inside the Hertzian cone crack area [I]. With a ceramic tile target, it is not possible to obtain any information during the test. Therefore a new geometry of ceramic target, called "Match was developed in order to put crack gauge inside the He...