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METAL PROCESSING
ArticleName Analysis of defects of industrial brass blanks
ArticleAuthor Pugacheva N. B., Ovchinnikov A. S., Lebed A. V.
ArticleAuthorData

Institute of Engineering Science of Ural Department of Russian Academy of Sciences, Ekaterinburg, Russia:

N. B. Pugacheva, Leading Researcher

 

JSC “Revda Non-Ferrous Metals Processing Works”, Revda, Russia:
A. S. Ovchinnikov, Chief Technologist (Technical Department)
A. V. Lebed, Engineer, Leading Auditor of Management Systems (Department of Certification, Standardization and Ecology)

Abstract

This article gives the results of analysis of types of defects, which appear during casting, cold rolling and drawing, and after hot pressing of alloyed wrought brass. Ways of these defects’ removing are described in terms of JSC “Revda Non-Ferrous Metals Processing Works”. There is shown the transition from one type of defect, which were not removed in initial processing stage, into another type, which leads to billet destruction on one of last processing stages. There was found that, usually, casting defects (such as blowholes, pores and bubbles) do not cause cracking, but during the pressure treatment they form bundles and form scabs, and decrease the density of semi-finished products and strength characteristics. A number of defects do not allow to put the ingot in hot pressure treatment in order to avoid defective production. Therefore, without the quality control of metals and metal-products, it is impossible to provide the 100% guarantee of reliable operation of expensive machines and responsible purpose constructions. Tubular billet normative documents provide the removal of surface defects, visible to naked eye, since the number of external defects, existing on the billet, is increased in proportion to increase in the pipe surface, and their removing from finished pipe surface reduces wall thickness. Therefore, it is more reasonable and easier to repair tubular billet than laminated tube. There was carried out an assessment of practical use of eddy-current method for definition of defects on “Foerster” flaw fault detection. The pros and cons of this method were determined, and according to them, the appropriate conclusions were made. Alternative methods of defects control are ultrasonic me thods, used for definition of surface and deep defects, cracks, sinks and separations in metallic and non-metallic materials. Low-intensity ultrasound is widely used for non-destructive testing of solid material products.

keywords Defect, brass, billet, casting, pressing, rolling, drawing, stamping, non-destructive testing
References

1. Volkogon G. M., Brezgunov M. M. Proizvodstvo slitkov medi i mednykh splavov (Manufacturing of copper ingots and copper alloys). Moscow : Metallurgiya, 1980. 100 p.
2. Osintsev O. E., Fedorov V. N. Med i mednye splavy. Otechestvennye i zarubezhnye marki : spravochnik (Copper and copper alloys. Russian and foreign grades : reference book). Moscow : Mashinostroenie, 2004. 336 p.
3. Voskoboynikov V. G., Kudrin V. A., Yakushev A. M. Obshchaya metallurgiya : uchebnik dlya vuzov (Basic metallurgy : tutorial for universities). Sixth edition, revised and enlarged. Moscow : Akademkniga, 2002. 758 p.
4. Tsyganov V. A. Plavka tsvetnykh metallov v induktsionnykh pechakh (Smelting of non-ferrous metals in induction furnaces). Moscow : Metallurgiya, 1974. 248 p.
5. Suchkov D. I. Med i ee splavy (Copper and its alloys). Moscow : Metallurgiya, 1967. 248 p.
6. Landikhov A. D. Proizvodstvo trub, prutkov i profiley iz tsvetnykh metallov : uchebnik dlya podgotovki rabochikh (Manufacturing of pipes, bars and profiles from non-ferrous metals : tutorial for workers’ training). Moscow : Metallurgizdat, 1952. 408 p.
7. Pugacheva N. B. Struktura i svoystva deformiruemykh legirovannykh latuney (Structure and properties of deformed alloyed brass). Ekaterinburg : Ural Department of Russian Academy of Sciences, 2012.
8. Tropotov A. V., Pugacheva N. B., Ryazantsev Yu. V., Zhukova L. M. Issledovanie ostatochnykh napryazheniy v izdeliyakh, izgotovlennykh iz slozhnolegirovannoy latuni (Research of residual stresses in products, manufactured from complex-alloyed brass). Metallovedenie i termicheskaya obrabotka metallov = Metal Science and Heat Treatment. 2006. No. 1. pp. 28–32.
9. Smirnov S. V., Pugacheva N. B., Soloshenko A. N., Tropotov A. V. Issledovanie plasticheskoy deformatsii slozhnolegirovannoy latuni (Research of plastic deformation of complex-alloyed brass). Fizika metallov i metallovedenie = The Physics of Metals and Metallography. 2002. Vol. 93, No. 6. pp. 91–100.
10. Pugacheva N. B. Struktura promyshlennykh (α+β)-latuney (Structure of industrial (α+β)-brass). Metallovedenie i termicheskaya obrabotka metallov = Metal Science and Heat Treatment. 2007. No. 2. pp. 23–29.
11. Pugacheva N. B. Pankratov A. A., Frolova N. Yu., Kotlyarov I. V. Strukturnye i fazovye prevrashcheniya v α+β-latunyakh (Structural and phase transformations in α+β-brass). Metally = Metals. 2006. No. 1. pp. 65–75.
12. Shevakin Yu. F., Seydaliev F. S. Stany kholodnoy prokatki trub (Cold pipe rolling mills). Moscow : Metallurgiya, 1966. 211 p.

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