“Red Metals” such as copper, brass, and bronze are physically different though similar in appearance to one another.
Copper has excellent electrical and thermal conductivity, which is why it is used in a wide range of products, and besides, it has good durability, formability as well as corrosion-resistance — the characteristic needed to manufacture pipes and pipe fittings. Not only can they be soldered and brazed at will, but many of them can also be welded using various gas, arc, and resistance methods, let along be polished and buffed to certain texture and luster you want.
Different grades of unalloyed copper vary greatly according to their impurities. Among them oxygen-free copper grades are the best for meeting the requirements of high conductivity and ductility. Unknown to most people, copper has excellent antibacterial properties.
According to the antimicrobial testing results conducted by the Environmental Protection Agency (EPA), 335 copper alloys, many brasses included, can kill almost all the bacteria within 2 hours of direct contact with them. More importantly, their antimicrobial effectiveness appears not to be influenced by normal tarnishing.
As one of the earliest metals discovered, copper was made into tools or adornments by Greeks and Romans. Furthermore, there is no lack of historical evidence of copper being applied to wound sterilization and drinking water purification.
It has been widely used in electrical wiring for almost 2 centuries since the invention of the electromagnet and the telegraph in the early nineteenth century. With the invention of telephone in 1876, widespread use of copper could be seen in telecommunications. Even today, copper electrical connectors are still used in power generation, distribution, and transmission due to its excellent electrical conductivity.
Brass is an alloy of copper and zinc that are combined in varying proportions, or with other elements, to achieve different mechanical and electrical properties and produce wide range of variation in color. The amount of zinc has a positive correlation with the strength and ductility of the alloy and can determine its various colors ranging from red to yellow.
Due to its resemblance to gold, brass is commonly used for decorations, and its high workability and durability are suitable for manufacturing musical instruments.
Other Brass Alloys
Tin brass is literally a brass alloy with tin added to prevent dezincification, i.e., the selective leaching of zinc from the brass alloy that leaves a fragile, porous structure. Such an alloy group includes an extensive array of metals, such as admiralty brass, naval brass, and free machining brass, that are characterized by low sensitivity to dezincification, moderate strength, high atmospheric and aqueous corrosion resistance as well as excellent electrical conductivity.
Due to their exceptional hot forgeability and cold formability, this group of alloys are extensively used for manufacturing fasteners, marine hardware, screw machine parts, pump shafts, and mechanical products that required high corrosion-resistance.
Bronze is formed by mixing copper with other ingredients than just tin, such as arsenic, phosphorus, aluminum, manganese, and silicon that can create various properties in a material that has a better solidity than does copper itself.
One can easily distinguish bronze from brass by their color features mainly because of bronze’s unique dull-gold color and faint rings on its surface.
In addition to its widespread use in the construction of sculptures, applications of bronze can also be seen in musical instruments, medals as well as industrial bushing and bearings where the low metal friction is required while its high corrosion-resistance contributes substantially to nautical applications.