Barkman, E. F.
Directorsymposium chairman, Reynolds Metals Co., Richmond, Va.
Pages: 2 Published: Jan 1970
For the past several years, ASTM Committee E-12 on Appearance of Materials has been studying the appearance of metallic surfaces. This work has been conducted by Task Group 4. The participants in this work soon realized that there existed no adequate and comprehensive compilation of techniques for describing the appearance attributes of metallic surfaces. Other materials have long been studied with respect to their appearance. For example, the color, texture, and visual appearance of white and colored textiles, papers, and paints have been well defined, and ASTM test methods for measuring chromatic attributes and gloss can be found in the Book of Standards. The metallic surfaces, however, presented a uniquely different problem of measuring the appearance. Most metallic surfaces have very little or no chromatic attributes. Or at least the chromatic features are not of major importance to describe the visual properties of metals. Instead, metals exhibit the features which the consumer generally refers to as “brightness.” This term, which is somewhat of a misnomer for describing what the eye first notices about metals, is one of the problems of accurate definitions confronting the workers in this field. In the past several years the metallic appearance of bare and coated metal products has developed an increasingly larger importance to consumer products such as automotive and appliances. Other product areas, such as jewelry and other decorative items, are examples where the metallic appearance is a primary characteristic of consumer appeal of the product. The space age also introduced needs for measuring and defining the optical properties of metallic surfaces as related to reflectors, surfaces to provide thermal balance in space vehicles, and the characteristics of metallic surfaces with respect to electromagnetic radiation and reflection outside the visible spectrum. This publication, however, will present results and findings of workers who are primarily concerned with the materials most commonly used for consumer products such as aluminum and stainless steel. It should be emphasized, however, that the discussions on the appearance and measurement of metallic surfaces, though giving heavy emphasis to aluminum and stainless steel can be applied usually to other metals such as plated coatings (whether on metal or plastic substrates) including chromium, nickel, and silver, and any other metal surface where it is desirable to describe the metallic appearance.
Paper ID: STP47440S