Difference between revisions of "9. What two metals were combined to make bronze? What effect of bronze on armaments?"

Revision as of 23:01, 18 January 2016

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Bronze is of exceptional historical interest and still finds wide applications. It was made before 3000 bc, though its use in artifacts did not become common until much later. The introduction of bronze was a huge improvement in tool and weapon manufacture. Unlike iron which was a difficult material to work with, bronze technologies were similar to the techniques improved during the copper age: It could be cast, hammered cold, and annealing improved its toughness. Bronze is an alloy of copper and of about 4% tin. It is harder than pure copper, melts at a lower temperature and is easier to cast. But when the amount of tin is 5% or higher the alloy becomes brittle when hammered and has to be annealed frequently. Bronze is harder than copper as a result of alloying that metal with tin or other metals. Bronze is also more fusible (i.e., more readily melted) and is hence easier to cast. It is also harder than pure iron and far more resistant to corrosion. The substitution of iron for bronze in tools and weapons from about 1000 bc was the result of iron’s abundance compared to copper and tin rather than any inherent advantages of iron.

http://www.reshafim.org.il/ad/egypt/trades/metals.htm

http://school.eb.com/levels/high/article/16617