Aluminum powder

Description

Ground flakes of Aluminum or an aluminum alloy that are used for metallic paints. Aluminum powder is made by grinding sheets of aluminum to form thin shiny flakes. It was probably first made in the mid-19th century but did not become popular as a paint pigment until about 1920. When dispersed in Oil or Varnish, the surface tension caused the flakes to spread out flat over the painted surface thus forming a near continuous metallic film. The aluminum pigmented films provide good moistureproofing and produce a surface that is 60-75 percent reflective. The paint film is durable and does not tarnish, but it lacks the luster of Silver, so it is generally not used for gilded decoration. Aluminum pigment paints were used for coating picture frames, radiators, roofs, and tanks.

Synonyms and Related Terms

aluminum bronze powder; aluminum metal pigment; poudre d'aluminium (Fr.); polvere d'alluminio (It.); pó de alumínio (Port.)

Physical and Chemical Properties

• Shape = irregular;
• Size = approximately 1 micron
• Reflected light = shiny;
• Transmitted light = opaque

Resources and Citations

• R. J. Gettens, G.L. Stout, Painting Materials, A Short Encyclopaedia, Dover Publications, New York, 1966 Comment: p. 92

• G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 48

• Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)