Bakelite (PF)

Bakelite is a thermosetting plastic, it’s made of resin and it was developed in 1907 by a Belgian chemist. Its main properties are hardness, rigidity and resistance to chemical products. Bakelite is electrically nonconductive and heat-resistant and this is why it’s used in radios, telephones (photo) and electrical insulators, and also in a wide variety of products as kitchenware, jewellery, pipe stems and children’s toys. Apart from this applications Bakelite is used for insulators in the electrical industry, motherboards and adhesives for plywood and so many more applications.

Here I attach a simple but clear video about the origin of Bakelite:

http://www.youtube.com/watch?v=3hF4XZxD37g

Teflon (PTFE)

Teflon is a synthetic material. Being exact it’s a thermoplastic polymer, made mainly of carbon and fluorine. This material is incombustible, resistant to chemical products and heat, with a low friction rate and it’s nonstick. It’s a white solid at room temperature but its mechanical properties degrade above 260°C.

It’s mainly used to nonstick surface of cooking utensils and laboratory apparatus, antifriction pieces of bearings and sheathings of high heats.  It can also be used in all these applications: planes and rockets covering because of its resistance to temperature changes. In the medicine sector it’s used for prosthesis because it doesn’t react with other substances or muscles and it’s also used for lining of pipes, as you can see in the photo. More applications are paints and varnishes.

Here I attach a video showing how to apply a Teflon tape:

http://www.youtube.com/watch?v=6zkh1IgBWvg&feature=related

Tin

Tin is a non-ferrous material and it’s mostly silvery. Its main proprieties are its malleability and ductility. It’s soft, resistant to corrosion but with a low resistance to efforts. Its main applications are two: steel laminates covering (can, tin) and soldering. Tin has also different alloys: bronze (with copper), soldering (lead), with bismuth and antimony, and it’s used mostly for electrical fuse blew and antifriction materials. As tin has a really low fusion temperature it’s easy to malleable and so make pieces in difficult shapes.

Lead

Lead is a non-ferrous material and it’s the densest one, and because of this lead is used for protection for noises, X-rays and gamma rays. Its melting temperature is so low that it’s easy to mould in complicated shapes like little pieces of chess, bullets. It has another important propriety: lead doesn’t tend to corrode with air, water and acids, what makes it useful for fountains and antioxidant paints. Lead is a very useful metal but it has a problem: it is toxic and pollutant. In the past lead was used for pipes but when it was known that it was toxic, industries started to make them of plastic. If we ingest lead, even an extremely small and tiny particle, it’s toxic for us and we can’t expel it from our body. So we have to be very careful with it.

Copper

Copper is a non-ferrous material and it’s one of the few that is found on its own in nature. Its main characteristics are that it’s soft, ductile and malleable. It’s easy to work with when it’s cold but it has acrimony, hardness, resistance and fragility. It has a really high level of thermal and electrical conductivity. It’s very resistant to corrosion and easy to recycle. You can make alloys with copper like bronze (copper and tin), which increases mechanical properties and it’s less conductive and it’s used for statues and musical instruments; or brass (copper and zinc), which increases mechanical properties and it’s more conductive and it’s used for locks and taps.

It has wide applications, and most of it it’s used for electrical cables, radiators, cauldron, water and gas tubes… In the past, it was used for cowbells and oil lamps, as you can see in the photos.

Steel

Steel is a ferrous material alloy that consists mainly of iron, with a little part of carbon, exactly between 0.1 and 1.76%. It’s found on the Earth’s crust only as iron ore combined with other elements such as oxygen or sulphur. Varying the amount of alloying elements you can control qualities such as hardness, ductility and tensile strength. Steel the most carbon it has, the harder and stronger it is, but it’s also less ductile than iron. Steel is really hard to mould but you can laminate and work it. Its main characteristics are its ductility, malleability, hardness and its medium resistance.

Steel is widely used in the construction of roads, railways, and other infrastructures like beams and girders, as you can see in the photo. Most large modern structures as stadiums, bridges and airports have a steel skeleton. In addition, it’s used in cars. Despite the increasing use of aluminium, steel is still the main material for cars bodies.

Presentation

Hi everybody! My name’s Aina and I’ve studied in La Llauna since I was in ESO 1. At the moment I’m doing Technology because when I finish secondary school I’d like to study engineering or architecture so I’m interested in anything related to this. I really enjoy travelling around the world and know how other cultures talk and celebrate their festive seasons. A perfect example is my journey to Dublin last summer, where I went to learn English with a native family, as you can see in the photo. I also love music and it means a lot to me because I’ve played the piano for ten years in the Conservatori.

This is my school Technology Blog and I will post technological information like characteristics of materials, mechanisms, components…

This ends here and I hope you all read my blog soon and you like and enjoy it!

See you soon!