Properties Of Metal Ceramic Alloys

The purpose of this article is to review basic information about the alloys used for fabricating metal ceramic restorations in dentistry.

Properties of metal ceramic alloys.

In addition to reviewing traditional noble metal and base metal metal ceramic alloys titanium and gold composite alloys are also discussed. Their compositions properties advantages and. Individual pure metals may possess useful properties such as good electrical conductivity high strength and hardness or heat and corrosion resistance. A cermet is a composite material composed of ceramic and metal materials.

Porosity also we refer pore size these are very important parameters for the ceramic material. Generally physical properties are identified by simple methods such as odour colour and physical form of the material solid liquid gas. Gold platinum palladium alloys were the first alloys used in metal ceramic restorations. The purpose of this article is to review basic information about the alloys used for fabricating metal ceramic restorations in dentistry.

The metal is used as a binder for an oxide boride or carbide. Generally the metallic elements used are nickel molybdenum and cobalt. Base metal alloys tend to have larger grain sizes and do not include grain refiners. Colorcolor noble metal contentnoble metal content hardnesshardness yield strengthyield strength elongationelongation fusion temperaturefusion temperature 125.

Sag and creep test the specimens were designed to reflect dimensional changes that may occur after each porcelain firing cycle and would in clude any mismatch between porce lain and metal that might occur. Their compositions properties advantages and disadvantages are presented and compared. Gold is the most abundant metal within the alloy 88 whereas concentrations of platinum and palladium are variable. Other physical properties of ceramics are.

Silver alloys have a major disadvantage in that they tarnish and corrode. A cermet is ideally designed to have the optimal properties of both a ceramic such as high temperature resistance and hardness and those of a metal such as the ability to undergo plastic deformation. They have variable properties and care must be taken in the selection as some are quite ductile and are unsuitable for use in load bearing areas of the mouth. Depending on the physical structure of the material cermets can also be metal matrix.

Commercial metal alloys attempt to combine these beneficial properties in order to create metals more useful for particular applications than any of their component elements.