roughened

Roughened is the past participle adjective of the verb roughen, used to describe a surface, edge, or material texture that has been made rougher than its original state. A roughened surface contains irregularities at microscopic or macroscopic scales, intended to increase friction, adhesion, or tactile texture, or to prepare a substrate for subsequent coatings.

Roughening can be achieved by mechanical, chemical, or combined methods. Mechanical roughening includes sandblasting, grinding, brushing, milling, or shot peening, which produce pits, grooves, or a textured topography. Chemical roughening uses acids, alkalis, or other etchants to selectively remove material and create a rough microstructure. Some processes combine both approaches to tailor roughness.

Surface roughness is quantified by parameters such as Ra (average roughness), Rz (average peak-to-valley height), and Rt (total height of roughness). Roughened surfaces are typically specified with roughness tolerances and assessed with profilometry, optical or atomic-force microscopy, or tactile measurements.

Industrial applications include improving adhesion of paints, coatings, adhesives, and composite materials; increasing friction in fasteners or bearing surfaces; and promoting tissue integration in dental and orthopedic implants. Roughened textures are also used in wood finishing, textiles, and electronics for grip, wear characteristics, or solderability.

Excessive roughening can introduce stress concentrations, reduce structural strength, trap contaminants, or accelerate wear. Process control and surface characterization are essential to ensure the roughness meets functional requirements and to avoid unintended degradation of performance.