Weathering

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MFA Acc. #: 76.742

Description

The mechanical or chemical processes by which a material deteriorates when exposed to outdoor conditions. Mechanical weathering includes the effects due to temperature variations (expansion, contraction, freeze-thaw, etc.), moisture changes (hydration, dehydration, etc.), and abrasion (wind, erosion, wear, etc.). Chemical weathering includes the effects due to reactions with oxygen, carbon dioxide, water, and pollutants. Heat and ultraviolet light from the sun can accelerate degradation.

Weathering

Synonyms and Related Terms

Verwitterung (Deut.); vieillissement (Fr.); meteorização (Port.)

Authority

• Theodore J. Reinhart, 'Glossary of Terms', Engineered Plastics, ASM International, 1988

• The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998

• Encyclopedia Britannica, http://www.britannica.com Comment: "weathering." Encyclopædia Britannica. 12 Oct. 2004 .