Localized magnesium alloys

The TH3 core is ignited by the primer, and the burning core then melts and ignites the magnesium alloy body of the bomb. The incendiary action on the target is localized. There is Utde scattering of the incendiary material. 

ACUTE HEALTH RISKS irritation of eyes, skin, and respiratory system cough particles of metallic magnesium or magnesium alloy that perforate the skin may produce a severe local lesion characterized by acute inflammatory reaction and evolution of gas. 

G. Baril, C. Blanc, M. Kedam, N. Pebere, Local electrochemical impedance spectroscopy applied to the corrosion behavior of an AZ91 magnesium alloy, J. Electrochem. Soc. 150 (2003) B488-B493. 

Magnesium alloys are highly susceptible to galvanic corrosion. Galvanic corrosion is usually observed as heavy localized corrosion of the magnesium adjacent to the cathode (Froats et al., 1987). Cathodes can be external, e.g. other metals in contact with the magnesium, or internal, e.g. second or impurity phases. These two kinds of galvan-... 

Ghali E, Dietzel W and Dietzel K-U (2004), Testing of general and localized corrosion of magnesium alloys a critical review , Jourruil of Materials Engineering and Performance, 13(5), 517-529. 

This chapter presents the current trends in this area with emphasis on load-bearing orthopaedic and dental implants. A detailed account on the general and the localized corrosion of conventional metalhc implants is provided. Novel fabrication strategies of nanostructured hydroxyapatite-based coatings and their roles as barrier coatings are presented. Impacts of nanoscale surface modifications on the corrosion resistance of permanent implants and novel bioresorbable implants based on magnesium alloys are highhghted. 

Localized electrochemical study of corrosion inhibition in microdefects on coated AZ31 magnesium alloy. Electrochim Acta 2010, 55(19), 5401-5406 (c) Bastos, A. C., Taryba, M. G., Karavai, O. V., Zheludkevich, M. L., Lamaka, S. V., Ferreira, M. G. S., Micropotentiometric mapping of local distributions of relevant to corrosion studies. Electrochem Commun 2010,12(3), 394—397. 

Galicia, G., N. Pebere, B. Tribollet, and V. Vivier, Local and global electrochemical impedances apphed to the corrosion behaviour of an AZ91 magnesium alloy. Corrosion Science, 51, 2009, 1789. 

Severe corrosion may occur in active A1 or Mg alloys in neutral solutions of heavy metal salts (salts of Cu, Fe, or Ni). This type of corrosion occurs when the heavy metal salts plate out to form active cathodes on the anodic magnesium surface. This type of galvanic corrosion can lead to localized pitting corrosion. 

It is well known that aluminum as such is fairly passive, because a very dense and uniform aluminum oxide AI2O3 layer is formed onto the metal to protect the metal from corrosion. Highly ductile light weight aluminum alloys that are passed through specific heat treatments can, however, make aluminum susceptible to corrosion. These materials may contain alloying elements such as magnesium and/or copper, which alter and complicate the corrosion behavior of aluminum. Typical forms of corrosion for the alloys are localized and pit corrosion. Due to the dense structure of the aluminum oxide layer, the corrosion rate of aluminum alloys is, however, substantially slower compared with corrosion/dissolution of CRS or HDG steel [15]. 

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