kulumisvastus

Kulumisvastus, in Estonian, refers to the wear resistance of a material—the ability to resist material loss when subjected to sliding, abrasive, or erosive contact. In engineering and materials science, kulumisvastus is a key performance criterion for components that experience surface degradation during operation, such as gears, bearings, seals, cutting tools, and hydraulic parts.

Wear can occur through several mechanisms, including abrasive wear from hard particles cutting or plowing the surface, adhesive wear from bonding and material transfer between contacting surfaces, surface fatigue wear from repeated loading, and erosive wear from high-velocity particle impacts. The level of kulumisvastus depends on factors such as hardness, toughness, microstructure, and the presence of protective coatings, as well as operating conditions like load, speed, temperature, lubrication, and the environment. A common trade-off is that increasing hardness can improve wear resistance but may reduce toughness, so optimized materials balance hardness, strength, and ductility. Surface engineering approaches, such as diffusion coatings, nitriding, or the application of hard coatings (PVD/CVD, ceramic or carbide coatings), are often used to enhance kulumisvastus without compromising the substrate.

Assessment of wear resistance typically involves standardized testing that measures material loss over sliding distance or time, such as pin-on-disk or ball-on-disk tests, and the Taber abrasion test. Results are reported as wear rates or volumes lost per unit load and distance. Common materials with high kulumisvastus include cemented carbides, advanced ceramics, hardened steels, and protective coatings. Understanding kulumisvastus guides material selection and surface treatment for durable, reliable components in harsh service environments.