Glossary

To reach 690 kPa (100 psi) air at 100% humidity, it is necessary to compress approximately 0.23 ml (8 ft.') of free air, with its inherent moisture, into 0.028 ml (one cubic foot), since atmospheric humidity is usually more than 12.5% at ambient. All undried compresed air systems at 690 kPa (100psi) and ambient temperatures are at 100% relative humidity.

Material applied to infiltrate and close the pores of a thermal spraying deposit. Secondary Gas. The minor or second constituent of the arc gas fed to the gun to produce plasma.

Those materials that exhibit the characteristics of forming a metallurgical bond with the substrate in the as-sprayed condition.

A protective device that partially shields an area of the work, thus permitting some overspray to produce a feathering at the coating edge.

The stress on the slip plane produced by external loads tending to slide adjacent planes with respect to each other in the direction parallel to the planes.

Protective gas used to prevent or minimize atmospheric contamination. See also Protective Atmosphere

A nonstandard term for residual stress.

See preferred term Screen

A method of determining particle size distribution, usually expressed as the weight percentage retained upon each of a series of standard screens of decreasing mesh size. See also Particle Size Distribution.

Point at which a self-fluxing alloy begins to shine during the fusing operation

The removal of oil, grease, and other soluble contaminants from the surface of the workpiece by immersion in suitable cleaners

The flaking or separation of a sprayed coating

A single thin flattened sprayed particle.

Extremely rapid, high rate of cooling, the effects of which can be observed in thermal spraying deposits leading to the formation of metastable phases and an amorphous microstructure.

A moving mass of dispersed liquid droplets or heat softened particles.

The angle of particle impingement, measured from the surface of the substrate to the axis of the spraying nozzle

See preferred term Exhaust Booth.

See thermal spraying deposit

The ratio of the density of the spray deposit to the theoretical density of the surfacing material. Usually expressed as percent of theoretical density.

A method for making thermal spray powder, especially ceramic powder, by spraying a slurry into a heated chamber and drying it to powder.

The rate at which surfacing material passes through the gun.

The order in which different layers of similar or different materials are applied in a planned relationship, such as overlapped, superimposed, or at given angles

The arc gas, ionized to form the plasma, is usually introduced into the arc chamber tangentially. The relatively cold gas chills the outer surface of the arc stream, tending to constrict the plasma, raise its temperature, and force it out of the anode (nozzle) in a steady, relatively unfluctuating stream.

To enhance, optimize and control coating properties influenced by parameter interaction.

The intentional overlapping of several workpieces in order that one protects or masks its neighbor during the blasting or spraying process.

To volatilize from the solid state to a gas.

Any material to which a thermal spraying deposit is applied.

Extra small, minute powder particles, usually less than five microns in size

The difference between the higher actual temperature at the evaporator outlet and the lower theoretical temperature of the refrigerant at pressure

Linear velocity of the thermal spray gun as it traverses the length of the workpiece. Also, the circumferential velocity of the substrate.

The operations necessary to produce a desired or specified surface condition.

A group of methods for producing irregularities on a surface. See also Dovetailing, Groove and Rotary Roughening, Rotary Roughening, Rough Threading, and Threading and Knurling.

The application by thermal spraying of a layer or layers of material to a surface to obtain desired properties or dimensions, as opposed to making a joint.

The material that is applied to a substrate during surfacing

The metal that is applied to a substrate during surfacing.