Properties Of Metal Ceramic Alloys

124 selection of metal ceramic alloysselection of metal ceramic alloys physical properties includes physical properties includes.

Properties of metal ceramic alloys.

Base metal alloys tend to have larger grain sizes and do not include grain refiners. Gold is the most abundant metal within the alloy 88 whereas concentrations of platinum and palladium are variable. Other physical properties of ceramics are. Colorcolor noble metal contentnoble metal content hardnesshardness yield strengthyield strength elongationelongation fusion temperaturefusion temperature 125.

Generally physical properties are identified by simple methods such as odour colour and physical form of the material solid liquid gas. The purpose of this article is to review basic information about the alloys used for fabricating metal ceramic restorations in dentistry. In addition to reviewing traditional noble metal and base metal metal ceramic alloys titanium and gold composite alloys are also discussed. Generally the metallic elements used are nickel molybdenum and cobalt.

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. Porosity also we refer pore size these are very important parameters for the ceramic material. 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. 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.

The metal is used as a binder for an oxide boride or carbide. Depending on the physical structure of the material cermets can also be metal matrix. A cermet is a composite material composed of ceramic and metal materials. Materials and methods four commercially available metal ceramic alloys representing a cross section of the types of alloys used were selected for the study table 1.

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. They were largely discontinued due to the introduction of cheaper alloys with improved mechanical properties and greater flexural strength. 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.

Individual pure metals may possess useful properties such as good electrical conductivity high strength and hardness or heat and corrosion resistance.