hærdende

Hærdende is a Danish term used primarily as an adjective or participle meaning "hardening" or "curing." It derives from the verb hærde, to harden. The word is used across several technical domains to describe processes, materials, or substances that cause or undergo hardening.

In polymer chemistry and materials engineering, hærdende refers to substances that initiate or promote curing of polymers and composites. A hærdende stof or hardener is mixed with a resin to produce a crosslinked network. Curing can be chemical, thermal, or radiation-based. Examples include amine or anhydride hardeners for epoxy resins, peroxide initiators for thermoset plastics, and UV-hærende systems for surface coatings that cure under ultraviolet light. Important terms include pot life, peak exotherm, and cure time.

In metallurgy and heat treatment, hærdning is the hardening of metals, especially steel, through heating and subsequent quenching and tempering. Hærdende stål may refer to steels capable of hardening to higher hardness levels, such as martensitic steels. The process changes microstructure and increases hardness and strength, often with trade-offs in toughness and ductility.

In civil engineering, concrete and cement hardening is often described as curing as well, referring to hydration reactions that gain strength over time, typically measured over days to weeks under appropriate moisture conditions.

English translations of hærdende depend on context, commonly "hardening" or "curing," and "hardener" for a substance used to promote curing. The term reflects the broader concept of transitioning from a pliable or liquid state to a rigid, durable state.