Evolution of Materials: From Stone Age to Nanotechnology
The History of Materials
The history of mankind has been linked to the use of materials. For consideration, we divide history into periods, with names that refer to materials: Stone Age, Copper Age, Bronze Age, and Iron Age.
- Stone Age: Characterized by the use of simple materials: bones, pottery, knives, arrows, and spears of flint.
- Copper Age: Copper is obtained from malachite or chalcopyrite.
- Bronze Age: Bronze is created by mixing copper with small amounts of tin.
- Iron Age: The technology of producing iron, which is more complicated, was the last to appear, using certain minerals such as limonite or magnetite.
The Consumer Society
Throughout the twentieth century, new needs began to appear through economic growth. The consumer society means that today no one can dispense with many electronic devices for domestic work, communication, or transportation.
Electronics and Construction
In the field of electronics, scientists look for materials to replace silicon. Second-generation organic materials and inorganic materials that have the properties of silicon have recently been developed. In construction, the need for highly resistant materials—to withstand major earthquakes—or good insulators has led to the use of composites.
Corrosion
Corrosion is a major cause of the destruction of many materials used in human activities. Corrosion occurs because the metals used are not stable; they are extracted from ores in which metals are combined as oxides, carbonates, sulfates, etc. Moreover, atmospheric components, especially oxygen, alter most materials through oxidation.
Advanced Materials
Carbon Fiber
A material consisting of woven carbon threads. Its resistance is three times the density of steel, and its weight is 4.5 times lower. It is very tough and barely altered by corrosion and fire. Carbon fiber has many types, depending on the temperature used to obtain them.
Superconductors
A class of materials whose electrical resistance and energy loss approach zero when they do not oppose the current flow, especially at temperatures near absolute zero (-273 ºC).
Other Applications of Nanotechnology
Energy applications may include longer battery duration, less contaminating energy sources, and greater efficiency. Chemical combustion reactions and electrolysis can be improved by using catalysts with nanoparticles. Applications in various industries include trials for food products to give an appearance of quality and fresh, long-lasting foods, eternal lights, etc.
Limitations and Risks of Nanotechnology
Atoms are made of particles, but we cannot forget their wave nature, so they can accelerate in certain circumstances and escape manipulation. Nanotechnology could become very complex and not only bring positive surprises. We must take into account the social and ethical issues.
The Landfill
The landfill is a solution currently being considered for the treatment and disposal of Municipal Solid Waste (MSW), although it is not the only one. For controlled landfill discharges, they must:
- Be sited on impervious soils or artificially waterproofed.
- Have a system for collecting liquids that circulate within the landfill.
- Have a regular burial system in operation.