Desgast

Desgast is the term used to denote the process by which a surface or component loses material or experiences degradation as a result of use, mechanical action, or environmental exposure. In practice, the concept is usually described with the Spanish or Portuguese word desgaste, and similar terms appear across Romance languages to denote wear. The phenomenon is central to materials science, mechanical engineering, and maintenance, since wear can affect performance, efficiency, and safety.

Wear results from several mechanisms. Abrasive wear occurs when harder asperities plow into a softer material. Adhesive wear arises from material transfer between surfaces under high contact stress. Surface fatigue wear derives from repeated cyclic loading, causing microcracks and flaking. Corrosive wear combines chemical attack with mechanical action, while erosive wear involves particulate impact or fluid jetting. Fretting wear occurs at small oscillatory displacements between contact surfaces.

Measurement and prognosis rely on indicators such as mass loss, wear depth, dimensional change, surface roughness, and changes in the coefficient of friction. Wear rates depend on load, slide distance, hardness, lubrication, temperature, and material pairings. Practical mitigation includes proper lubrication, selection of harder or more compatible materials, surface hardening or coatings, protective finishes, design changes to reduce contact stresses, and environmental controls. Applications span engines, bearings, gears, cutting tools, seals, and structural components. Monitoring and maintenance strategies—inspection, vibration analysis, lubrication scheduling, and predictive life estimation—help prevent unexpected failures due to desgaste. See also wear, corrosion, erosion.