highroughness
High roughness refers to surfaces whose topographical deviations from a reference plane are large relative to a chosen scale. It is usually expressed using roughness parameters such as Ra, which denotes the arithmetic average of absolute departures from the mean line over a sampling length, or Rq, RMS roughness, and Rz, which represents the average of peak-to-valley heights. In practice, 'high' is relative to the functional requirement; a surface may be high roughness for optical applications but acceptable for anti-slip floors.
Measurement and characterization: Roughness is measured by profilometry (contact stylus or optical) and by various instruments
Causes and production: High roughness can arise from manufacturing processes such as milling, turning, sandblasting, shot
Effects and applications: High roughness increases surface area, friction, wear, and adhesion. It can improve grip
Context and considerations: In tribology, high roughness often raises friction and wear; in optics and coatings,