A blister that occurs in the core of clad products.

Measure of the displacement of the center of the core relative to the cladding center.

Measure of the non-roundness of the core.

That part of the electrical energy required to magnetize a core of magnetic material that is dissipated as heat generated within the core, as distinguished from the energy lost in the coil surrounding the core.

Another name for the extruder tips used when extruding a plastic or rubber insulation coating on wire with an extrusion machine. Alternatively, the tube into which the die tips screw.

The center strand of a stranded conductor, around which the outer strands are wrapped in spiral layers. Employed as core or foun­dation wire in certain types of wire rope construction. Drawn to various sizes and usually fully annealed for ordinary strand ropes, but for certain constructions a hard, high-carbon wire, finished to a specified tensile stress, is employed. Also, the wire used in the construction of sand cores placed in molds for the production of castings. This is a low-carbon steel wire, fully annealed at finished size and with a black annealed finish or cleaned and oiled.

Core member of a wire rope about which the strands are laid. It may be fiber, a wire strand or an indepen­dent wire rope.

Tungsten carbide die blanks that are prepared with a preformed hole before sintering, reducing drilling time considerably. The smallest holes pre­formed are about 0.004-5 in. (0.1–127 mm); below this, holes have to be drilled in the solid blank.

Cracks that initiate at the corner of a square or rectangular section of metal and proceed toward the center. They can form in a cast billet section as a response to cooling dynamics. Corner cracks can also form or open during hot rolling operations.

A visible electrical discharge from a conductor in the form of a “blue glow,” caused by sharp edges of damaged spots in a high-voltage line. It is more obvious when the conductor is bare and has a profile of a sharp point or edge. It is disruptive to line-of-sight signals such as antenna T.V. and radio.

See Voltage, Corona Extinction.

The critical value in the application of an electrical potential where a corona is first observed.

The minimum value of falling rms voltage that sustains electrical discharge from surface irregularities of bare cable or within the vacuous or gas filled spaces in the cable construction or insulation.

The total time that an insulation system, placed in a high voltage electrical field that leads to continuous coronoa discharge, can remain in corona discharge before total dielectric discharge failure occurs.

Chemical action that causes destruction of the surface of a metal by oxidation or chemical combination. Gradual chemical or electrochemical attack on a metal by atmosphere, moisture or other agents.

The severe loss of ductility of a metal resulting from corrosive attack, usually intergranular and often not visually apparent.

Cracking produced by the combined action of repeated or fluctuating stress and a corrosive environment.

Methods that provide some degree of protection to metal. These include protective atmospheres, other metals, coatings (such as paint), and dissimilar metals that corrode to protect another metal.

Intense corrosion that occurs when a base metal (reactive) is in contact with a more noble (unreactive) metal. This process is associated with a galvanic cell that is set up with the base metal as an anode.

Pertaining to polymer extrusion, it is the accelerated wear on moving parts (such as screw and barrel surfaces) caused by chemical attack, which is in addition to frictional wear. The corrosive chemical can be created when polymers like FEP PVC degrade due to overheating.