Flakes are easy to make, but not always easy to make in the desired shape and size. Some manufacturing processes produce flakes with an inherent microscopic curvature, which are susceptible to cracking under transverse loads during fabrication into flat or molded shapes. The number of materials used in flake composites is limited, most metal flakes are aluminum. And also all flakes can be used with a wide variety of organic or inorganic binders or matrixes as long as the material has chemical, mechanical processing.
Glass-Flake Composites. Is a Glass-flake composite which reinforced plastics and laminate with small size, thin films or flakes of glass. The properties are below:
High flexural modulus since flakes are free to bend in only one plane
Uniform mechanical properties in the plane of the flakes
Higher strength because flakes can be packed to higher density
Lower moisture, liquid, and vapor transmission thanks to the labyrinthine structure
Higher dielectric strength and resistance to heat
Lower cost because flakes are less expensive to make than glass fiber or cloth
Mica Flake Composites. Mika flakes are the most familiar and widely used flake materials. Although less versatile than glass flakes for structural and moisture-barrier applications, they are much more useful where a combination of dielectric strength and heat resistance is needed. Natural or synthetic mica flakes are available in an extremely large range of shapes and size. Mica splittings remain in their original position after the binder has volatilized and insulate perfectly as long as the unit is undisturbed and compression.
Metal-Flake Composites. Metal flakes can be used in a matrix to provide impermeable barriers and corrosion resistance, to impart thermal and electrical conductivity to the composite. Metal-flake production initially was confined principally to aluminum and silver, which probably the greatest deterrent to development of a wider variety of metal flakes has been the relative difficulty of producing them. Silcon carbide, Cuprum Aluminum, aluminum diboride, etc.
Graphite-Flake Composites. A cast iron with an intermediate strength, good machinability, thermal properties and castability is called compact-flake-graphite iron. Although the graphite in compact-flake-graphite resembles that of gray iron, the flakes are shorter, thicker and more rounded at the edge.
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