CD Source Closed Drift ion source CIM Ceramic Injection Moulding, a production technique where ceramic powders are mixed with a plastic into a pliable paste and forced into a mould. CNC Machining Computer Numerically Controlled Machining CVD Chemical Vapour Deposition, a production technique involving the reaction of gaseous chemicals, the product of which will deposit onto a prepared substrate. DLC Diamond-Like Carbon Glaze A surface coating that seals any open porosity of the bare ceramic surface from contamination or moisture pickup Ion Beam Deposition Applying a coating to a substrate by way of ion beam. MIM Metal Injection Moulding, very similar to CIM, this technique uses specially prepared metal powders to make metal components Poling The application of a high electric field resulting in dipole alignment within the material. Sintering The heating process that transforms a green ceramic and densifies the material into a stronger state. Materials Properties Coefficient of Thermal Expansion Either volumetric or linear this describes the expansion that occurs with a change in temperature. Volumetric describes the volume change whereas linear describes the change in dimensions. Dielectric Strength The minimum electric field that produces breakdown of the insulating properties of the dielectric. Green Ceramic/ Green Body A ceramic part in an unfired state Hermetic Seal Airtight seal Poisson’s Ratio When a sample of material is stretched in one axis, it tends to get thinner in the other two axes. Poisson's ratio (ν) is a measure of this tendency. It is defined as the ratio of the strain in the direction of the applied load to the strain normal to the load. For a perfectly incompressible material, the Poisson's ratio would be exactly 0.5. Porosity The proportion of the non-solid volume to the total volume of material. Thermal Downshock Thermal downshock is the name given to cracking resulting from rapid temperature change. It occurs when a thermal gradient causes different parts of an object to expand by different amounts. This differential expansion can be understood in terms of stress or of strain, equivalently. At some point, this stress overcomes the strength of the material, causing a crack to form. If nothing stops this crack from propagating through the material, it will cause the component to catastrophically fail. Young’s Modulus Young's modulus (or elastic modulus) is a measure of the stiffness of a given material. It is defined as the limit for small strains of the rate of change of stress with strain. This can be experimentally determined from the slope of a stress-strain curve created during tensile tests conducted on a sample of the material. Young's modulus is named after Thomas Young the English physicist, physician, and Egyptologist Materials and Products PBN Pyrolytic Boron Nitride RBSN Reaction Bonded Silicon Nitride SSN Sintered Silicon Nitride ZTA Zirconia Toughened Alumina |