Aluminium bronze 2261503 204633120 2008-04-10T05:51:38Z Rei-bot 3258344 robot Adding: [[pt:Bronze-Alumínio]] [[Image:AlubronzeCuAl20v500.png|thumb|Aluminium bronze with 20% Aluminium, V=50:1]] '''Aluminium bronze''' is a type of [[bronze]] in which [[aluminium]] is the main [[alloy]]ing [[metal]] added to [[copper]]. A variety of aluminium bronzes of differing compositions have found industrial use, with most ranging from 5% to 11% aluminium by weight, the remaining mass being copper; other alloying agents such as [[iron]], [[nickel]], [[manganese]], and [[silicon]] are also sometimes added to aluminium bronzes. ==Compositions== Following is a list of common standard aluminium bronze [[wrought alloy]] compositions, by [[ISO 428]] designations (proportional composition by weight; copper is the remainder by weight and is not listed): {| class="wikitable" |- |Alloy |[[Aluminium]] |[[Iron]] |[[Nickel]] |[[Manganese]] |[[Zinc]] |[[Arsenic]] |- |'''CuAl<sub>5</sub>''' |4.0% - 6.5% |0.5% max |0.8% max |0.5% max |0.5% max |0.4% max |- |'''CuAl<sub>8</sub>''' |7.0% - 9.0% |0.5% max |0.8% max |0.5% max |0.5% max | |- |'''CuAl<sub>8</sub>Fe<sub>3</sub>''' |6.5% - 8.5% |1.5% - 3.5% |1.0% max |0.8% max |0.5% max | |- |'''CuAl<sub>9</sub>Mn<sub>2</sub>''' |8.0% - 10.0% |1.5% max |0.8% max |1.5% - 3.0% |0.5% max | |- |'''CuAl<sub>10</sub>Fe<sub>3</sub>''' |8.5% - 11.0% |2.0% - 4.0% |1.0% max |2.0% max |0.5% max | |- |'''CuAl<sub>10</sub>Fe<sub>5</sub>Ni<sub>15</sub>''' |8.5% - 11.5% |2.0% - 6.0% |4.0% - 6.0% |2.0% max |0.5% max | |} ==Material properties== Aluminium bronzes are most valued for their higher strength and [[corrosion]] resistance as compared to other bronze alloys. These alloys are [[tarnish]]-resistant and show low rates of corrosion in [[Earth's atmosphere|atmospheric]] conditions, low [[oxidation]] rates at high temperatures, and low reactivity with [[sulfur|sulfurous]] compounds and other [[exhaust gas|exhaust]] products of [[combustion]]. They are also resistant to corrosion in [[sea water]]. Aluminium bronzes' resistance to corrosion rests in the aluminium component of the alloys, which reacts with atmospheric [[oxygen]] to form a thin, [[tough]] surface layer of [[alumina]] (aluminium oxide) which acts as a barrier to corrosion of the copper-rich alloy. Another notable property of aluminium bronzes are their [[biostatic]] effects. The copper component of the alloy prevents colonization by marine organisms including [[algae]], [[lichen]]s, [[barnacle]]s, and [[mussel]]s, and therefore can be preferable to [[stainless steel]] or other non-cupric alloys in applications where such colonization would be unwanted. Aluminium bronzes tend to have a golden color. ==Applications== Aluminium bronzes are most commonly used in applications where their resistance to corrosion makes them preferable to other engineering materials. These applications include [[bearing brush]]es and [[landing gear]] components on [[aircraft]], [[engine]] components (especially for sea-going ships), underwater fastenings in [[naval architecture]], and ship [[propeller]]s. The attractive gold-toned coloration of aluminium bronzes has also led to their use in [[jewelry]]. Aluminium bronzes are in the highest demand from the following industries and areas: *General [[sea water]]-related service *[[Water supply]] *[[Oil]] and [[petrochemical]] industries eg tools for use in non-[[sparking]] environments *Specialized anti-corrosive applications *Certain [[structural retrofit]] building applications Aluminium bronze can be [[welding|welded]] using the [[metal inert gas welding|MIG]] welding technique with an aluminium bronze core and pure [[argon]] gas. Alloys similar to Aluminium bronze are used in making coins, for example the $1 and $2 [[coins of the Australian dollar|Australian coins]] produced by the [[Royal Australian Mint]] and the [[Nordic gold]] used for some [[Euro coins]]. ==References== *Copper Development Association. [http://www.cda.org.uk/megab2/corr_rs/pub80/default.htm "Publication Number 80: Aluminium Bronze Alloys Corrosion Resistance Guide"]. Retrieved [[July 18]] [[2005]]. *Copper Development Association. [http://www.cda.org.uk/megab2/corr_rs/pub80/default.htm "Publication Number 82: Aluminium Bronze Alloys Technical Data"]. Retrieved [[July 18]] [[2005]]. [[Category:Copper alloys]] [[Category:Bronze]] [[de:Aluminiumbronze]] [[it:Cuprallumini]] [[ms:Gangsa aluminium]] [[pt:Bronze-Alumínio]]