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Structure of an etched metal visible to the naked eye or at magnifications up to 10 diameters.
(science and technology)
The external forms of a structure that can be observed without magnification, for example, the cubic crystal form of sodium chloride.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(of a metal), the structure of a metal that is visible visually or under a magnifying glass (that is, under magnification of up to 25 X). The macrostructure is studied in flat samples, called templates, cut from an item or blank, and also on the fracture surfaces of articles. To reveal the surface structure of a template, it is polished carefully and then etched with solutions of acids or alkalies.

The study of the macrostructure reveals discontinuities in the metal (cavities, porosity, gas bubbles, stratification, and fissures), distribution of impurities and nonmetallic inclusions, shape and distribution of crystallites (grains) in various parts of the item, and sometimes even the structural features of individual grains of the metal. Studies of the macrostructure lead to conclusions on the quality of initial materials and the correctness of the conduct of casting, pressure working, and welding processes. In some cases the quality of metals is characterized by the type of fracture, which makes possible determination of the path of the plane of fracture (through the body or along the grain boundaries) and of the causes of fracture.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Dans le cadre de cette recherche, les groupes (cluster) de documents sont analyses afin de detecter la ou les macrostructures permettant de les rassembler et qui, selon notre sous-hypothese, correspondent a une structure de type narratif.
Caption: Figure 2: The macrostructure of part of the 30 [micro]m/s withdrawn DS ingot showing the columnar structure (left) and dendritic structure (right).
This is a strategic use of macrostructure by the author to promote the existence of IFC to the readers as an organization which will support them if they want to renounce the religion.
This conviction is reinforced also by the result of rhizomorphs macrostructure comparison: rhizomorphs of local ecomorphotypes (see table 1) and representants of A.
As shown above, if [delta] is small, the waves are governed by the properties of the macrostructure, if, however [delta] is large, the waves 'feel' more microstructure (see for example [3]).
Van Djik (2009) refers to these social structures as "semantic macrostructures" and to daily interactions as "local meanings" (pp.
Despite the usefulness of elucidating the micro and macrostructures of the narrative texts, Ermida's specific reservation revolves around the normative rigidity of structuralist analysis in matters of ambiguity, which rules humor texts.
In macrostructures of welded stainless steel joints many small pores near the area of the weld root were observed.
The global processes, or the macrostructures, determine the overall meanings of the elements, or macrostructures, of the discourse.
1 to 3 document the macrostructures of penetration weld 1.2-1.5.
When referring to macrostructures (chapter 2), the book advocates their analytical character because that is what users (LSP students and translators) really need.