Which of the following are the metals of bronze alloy?
An alloy is a combination of metals like gold, copper, iron, tin, silver, or these metals with other non-metals like arsenic, phosphorous. The 'bronze' is an alloy consisting primarily of copper (Cu) and tin (Sn). Copper has a melting point (m.p) 1357.77 K (1084.62 deg C, 1984.32 deg F). Tin has m.p 505.08 K (231.93 deg C 449.47 deg F). The m.p of 'bronze' is about 950 deg C (1,742 deg F). The Bronze Age is the second principal period of the three-age, Stone-Bronze-Iron system, as proposed in modern times by Christian Jurgensen Thomsen. He was the first to establish an evidence-based division of prehistory into discrete periods. Bronze, an alloy of Cu and Sn, was the first alloy discovered, during this period.
The typical modern bronze is 88% Cu and 12% Sn. The alpha bronze alloys of 4-5% Sn are used to make coins, springs, turbines, and blades. In the Bronze Age, two forms of bronze were commonly used: ''classic bronze'', about 10% Sn, was used in casting; and about 6% Sn in ''mild bronze''. The resonance qualities of bell bronze are due to 20% Sn and 80% Cu. The high Sn content (23%) bronze alloy is colloquially known as bell metal. Bronze bells from Thailand and Cambodia date back to 3,600 BC. The tougher B8 bronze is made from 8% Sn and 92% Cu. The Temple bells donated to the Sangha (order of monks) was composed of 83% Cu and 17%Sn.