All metals share two main characteristics: ductility and malleability. Both are evident in different degrees depending on the metal. Ductility means the metal can be permanently drawn out into a long thin wire or thread without breaking. Malleability means the metal can be hammered into a shape or form or formed by pressure from rollers. Metals are good conductors of electricity and tend to be thermally conductive as well. They heat quickly, but also cool quickly, and are usually cool to the touch. Metals can be shiny or matte, depending on the type of metal and the surface treatment, but in general they tend to reflect light, giving them their characteristic luster. Metals also reflect sound, and can contribute to the acoustical liveliness of a space. Most metals have a protective layer of oxide, but will corrode or rust when exposed to atmospheric moisture or slowly develop a patina, the greenish film that develops over time on the surface of metals such as bronze and copper. Corrosion can be consistent across the surface or it may be localized, which results in pitting. Because it is a natural material, metal will move or undergo dimensional changes when subject to variations in temperature.
The mining and production of metal consumes energy, creates waste materials, and emits greenhouse gases. Ore deposits take many thousands of years to develop, so for all practical purposes, ore is a nonrenewable natural resource. Mining ore can be destructive to the environment, disturbing the land and disrupting biodiversity. The human cost of mining is high, not only when mining accidents occur but also in incidences of illnesses suffered by miners from exposure to fumes and other conditions in a mine. As with mining, the production methods that turn metal ore into a usable product can have harmful effects on workers. The process of producing metal uses a large quantity of fossil fuels, releasing contaminants into the atmosphere. For example, waste products from copper include arsenic and lead.
10 Best Home Gym Design Ideas Basement Photo Gallery
The metal production industry is aware of its negative environmental impact, and steps are being taken to mitigate it.
Mining companies strive to balance the financial need to mine the maximum amount of ore with the practical need to mine lower grades of ore, getting the most out of a mine so that less area needs to be mined. Better ventilation in mines is one of the improvements that has nearly eradicated black lung disease in workers.
A positive aspect of metal production is recyclability. Slag and cinders, by-products of iron ore production, are now reused as an aggregate for concrete and in asphalt and cement products. Steel, aluminum, and copper are easily recycled; copper and aluminum are 100 percent recyclable without any loss in quality. Because metal products are very durable, they have a long life. Finished metal products do not affect indoor air quality.
Maybe You Like Them Too
- Home Designs Elevation
- Decorating Ideas Joanna Gaines
- House Designs 5 Bedroom
- Decorating Ideas Brown Sofa
- Decorating Ideas Sunroom