my first prototype

this is my first prototype continued. so far, i have folded up my box. i have also made up brackets from scrap metal and have riveted them onto my box to hold it together. also, i have started a back cover to fit onto the back of the box(so the battery is hidden). the box has been bended using a metal bender machine and i have used a metal guilitine to cut out the brackets. a CAM machine was used to cut the box and back plate out. the solar panel will sit ontop of the box and the led's will be on either side of the solar panel

week 4 term 2

this week, i did some work on my final design on freehand. we are doing blogging. no school this friday

materials research bronze

Bronze
Traditional bronze is a copper alloy with up to 10% tin. The tin in bronze makes it more resistant to wear than unalloyed copper. Bronzes today are usually stronger and more resistant to corrosion than brass.

Contemporary bronzes are typically copper alloys that may contain silicon, manganese, aluminium, lead, iron and other elements, with or without tin.

The variations in bronze composition significantly affect its characteristics. Wearability, machinability, corrosion-resistance and ductility for deep drawing are often considered.

Bronze parts are typically used for bearings, clips, electrical connectors and springs. The Evans Company can stamp and deep draw from these alloys cost effectively, using high speed transfer and progressive presses.

Combro, or commercial bronze, is 90-10, or 90% copper/10% tin. It is frequently the least expensive, most easily obtained grade of bronze.

Aluminium bronze is a copper-aluminium alloy that may contain iron, nickel, and/or silicon for greater strength. It is used for tools and, because it will not spark when struck, for parts to be used around flammable materials. Aluminium bronze is frequently used for aircraft and automobile engine parts.

Manganese bronze is actually a brass containing manganese. It is often used for ship propellers because it is strong and resists saltwater corrosion.

http://www.evanstechnology.com/bronze.html

bronze is a coppery coloured material because it has copper in it. it is non-corrosive but it is not a good choice of material for the light that im making. this is an additional material that i have chose to research. it is expensive and it contrasts with aluminium.

materials research copper

As we saw at the beginning of this article, copper is Atomic Number 29, that is, an atom of copper has 29 protons. The Atomic Weight is 63.54. The Atomic Symbol is Cu.

Copper is in column IB of the Periodic Table of the Elements, above Silver (Ag) and Gold (Au). Elements in the same column have some similar properties. Like silver and gold, copper is soft (with a Moh's hardness of 2.5 to 3, that is, harder than a fingernail, but softer than a steel pocketknife). The surface has a metallic luster. With a specific gravity of 8.2 (based on the density of 8.2 grams per cubic centimeters, g/cm3), it is far denser than water with a specific gravity of 1, or sulfur, with a specific gravity of just over 2, or carbon in the mineral graphite (2.23). Silver, however, is below copper in column IB, and so it is denser (10.5) and gold, even lower, is far denser at 19.

When Copper combines with other elements, it has a charge of either +1 (called "cuprous") or +2 (called "cupric").

Physical Properties
Like gold and silver, copper is malleable. That is, it can be bent and shaped without cracking, when either hot or cold. It can be rolled into sheets as thin as 1/500 of an inch.

Copper also is ductile, that is, it can be drawn out into thin wire. A copper bar 4 inches thick can be heated, rolled, then drawn into a round wire so thin that it is thinner than a human hair. This wire is 20 million times longer than the original bar!

Industry valued copper for these properties. Copper is second only to silver in its ability to conduct electricity, but silver is too expensive for this sort of use. Bronze and brass, however, do not conduct electricity as well as pure copper.

Besides electricity, copper also is an excellent conductor of heat, making it an important metal in cookware, refrigerators, and radiators.

Copper is resistant to corrosion, that is, it will not rust. If the air around it often is damp, it will change from its usual reddish orange color to reddish-brown. Eventually, it is coated with a green film called a "patina" that stops all further corrosion.

The melting point of copper is 1083.4 degrees Centigrade. Liquid copper boils at 2567 degrees Centigrade.

http://www.unr.edu/sb204/geology/props.html

copper has a unique colour for a metal. it looks like a brown and is an excelent conductor. it is quite soft and it is kind of cheap. its non-corrosive, however it oxidises. a good choice for parts of a solar garden light

materials research brass

Brass is any alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties. In comparison, bronze is principally an alloy of copper and tin. Despite this distinction, some types of brasses are called bronzes. Brass is a substitutional alloy. It is used for decoration for its bright gold-like appearance; for applications where low friction is required such as locks, gears, bearings, ammunition, and valves; for plumbing and electrical applications; and extensively in musical instruments such as horns and bells for its acoustic properties.


Decorative bolt made in solid brass.
A decorative brass paperweight, left, along with zinc and copper samples. Brass has a muted yellow colour, somewhat similar to gold. It is relatively resistant to tarnishing, and is often used as decoration and for coins.

Brass has likely been known to humans since prehistoric times, even before zinc itself was discovered. It was produced by melting copper together with calamine, a zinc ore. In the German village of Breinigerberg an ancient Roman settlement was discovered where a calamine ore mine existed. During the melting process, the zinc is extracted from the calamine and mixes with the copper. Pure zinc, on the other hand, has too low a boiling point to have been produced by ancient metalworking techniques. The many references to 'brass' appearing throughout the King James Bible are thought to signify another bronze alloy, or copper, rather than the strict modern definition of 'brass'.[3]

The malleability and acoustic properties of brass have made it the metal of choice for brass musical instruments such as the trombone, tuba, trumpet, euphonium, and the French horn. Even though the saxophone is classified as a woodwind instrument and the harmonica is a free reed aerophone, both are also often made from brass. In organ pipes designed as "reed" pipes, brass strips are used as the "reeds".

Brass has higher malleability than copper or zinc. The relatively low melting point of brass (900 to 940°C, depending on composition) and its flow characteristics make it a relatively easy material to cast. By varying the proportions of copper and zinc, the properties of the brass can be changed, allowing hard and soft brasses.

Today almost 90% of all brass alloys are recycled. Because most brass is nonmagnetic, it can be separated from ferrous scrap by passing the scrap near a powerful magnet. Brass scrap is collected and transported to the foundry where it is melted and recast into billets. Billets are heated and extruded into the desired form and size.

Aluminium makes brass stronger and more corrosion resistant. Aluminium also causes a highly beneficial hard layer of aluminium oxide (Al2O3) to be formed on the surface that is thin, transparent and self healing. Tin has a similar effect and finds its use especially in sea water applications (naval brasses). Combinations of iron, aluminium, silicon and manganese make brass wear and tear resistant. A well known alloy used in the automotive industry is 'LDM C673', where the combination of manganese and silicon leads to a strong and resistant brass.


http://en.wikipedia.org/wiki/Brass

Brass is an alloy of copper and zinc, therefore making the colour a yellow colour. this makes brass look cool apart from the fact that it oxidises. however, it is non-corrosive but it is a bit expensive.
a good choice of material if you want the light to look cool

materials research stainless steel

Stainless steel's resistance to corrosion and staining, low maintenance, relative inexpense, and familiar luster make it an ideal base material for a host of commercial applications. There are over 150 grades of stainless steel, of which fifteen are most common. The alloy is milled into sheets, plates, bars, wire, and tubing to be used in cookware, cutlery, hardware, surgical instruments, major appliances, industrial equipment, a structural alloy in automotive and aerospace assembly and building material in skyscrapers and other large buildings. Orange juice tankers (sometimes also other chemical tankers) often have their tanks made of stainless steel.

Stainless steel is also used for jewelry and watches. The most common stainless steel alloy used for jewelry is 316L. It can be re-finished by any jeweler and, unlike silver, will not oxidize and turn black.

Stainless steel is 100% recyclable. In fact, an average stainless steel object is composed of about 60% recycled material, 25% originating from end-of-life products and 35% coming from manufacturing processes.[4]

Types of stainless steel

There are different types of stainless steels: when nickel is added, for instance, the austenite structure of iron is stabilized. This crystal structure makes such steels non-magnetic and less brittle at low temperatures. For higher hardness and strength, carbon is added. When subjected to adequate heat treatment, these steels are used as razor blades, cutlery, tools, etc.

Significant quantities of manganese have been used in many stainless steel compositions. Manganese preserves an austenitic structure in the steel as does nickel, but at a lower cost.

Stainless steels are also classified by their crystalline structure:

* Austenitic, or 300 series, stainless steels comprise over 70% of total stainless steel production. They contain a maximum of 0.15% carbon, a minimum of 16% chromium and sufficient nickel and/or manganese to retain an austenitic structure at all temperatures from the cryogenic region to the melting point of the alloy. A typical composition of 18% chromium and 10% nickel, commonly known as 18/10 stainless, is often used in flatware. Similarly, 18/0 and 18/8 are also available. Superaustenitic stainless steels, such as alloy AL-6XN and 254SMO, exhibit great resistance to chloride pitting and crevice corrosion due to high molybdenum contents (>6%) and nitrogen additions, and the higher nickel content ensures better resistance to stress-corrosion cracking over the 300 series. The higher alloy content of superaustenitic steels makes them more expensive. Other steels can offer similar performance at lower cost and are preferred in certain applications.[citation needed]

* Ferritic stainless steels are highly corrosion-resistant, but less durable than austenitic grades. They contain between 10.5% and 27% chromium and very little nickel, if any. Most compositions include molybdenum; some, aluminium or titanium. Common ferritic grades include 18Cr-2Mo, 26Cr-1Mo, 29Cr-4Mo, and 29Cr-4Mo-2Ni.

* Martensitic stainless steels are not as corrosion-resistant as the other two classes but are extremely strong and tough, as well as highly machineable, and can be hardened by heat treatment. Martensitic stainless steel contains chromium (12-14%), molybdenum (0.2-1%), nickel (0-<2%), and carbon (about 0.1-1%) (giving it more hardness but making the material a bit more brittle). It is quenched and magnetic. It is also known as series-00 steel.

* Precipitation-hardening martensitic stainless steels have corrosion resistance comparable to austenitic varieties, but can be precipitation hardened to even higher strengths than the other martensitic grades. The most common, 17-4PH, uses about 17% chromium and 4% nickel. There is a rising trend in defense budgets to opt for an ultra-high-strength stainless steel if possible in new projects, as it is estimated that 2% of the U.S. GDP is spent dealing with corrosion. The Lockheed-Martin Joint Strike Fighter is the first aircraft to use a precipitation-hardenable stainless steel—Carpenter Custom 465—in its airframe.

Duplex stainless steels have a mixed microstructure of austenite and ferrite, the aim being to produce a 50/50 mix, although in commercial alloys, the mix may be 40/60 respectively. Duplex steels have improved strength over austenitic stainless steels and also improved resistance to localised corrosion, particularly pitting, crevice corrosion and stress corrosion cracking. They are characterised by high chromium (19–28%) and molybdenum (up to 5%) and lower nickel contents than austenitic stainless steels.

http://en.wikipedia.org/wiki/Stainless_steel

stainless steel is a non-corrosive metal and is abit more expensive then aluminium. it is an average choice for the solar garden light.

materials research aluminium

Aluminium is a soft, durable, lightweight, malleable metal with appearance ranging from silvery to dull gray, depending on the surface roughness. Aluminium is nontoxic, nonmagnetic, and nonsparking. It is also insoluble in alcohol, though it can be soluble in water in certain forms. The yield strength of pure aluminium is 7–11 MPa, while aluminium alloys have yield strengths ranging from 200 MPa to 600 MPa. Aluminium has about one-third the density and stiffness of steel. It is ductile, and easily machined, cast, and extruded.

Corrosion resistance is excellent due to a thin surface layer of aluminium oxide that forms when the metal is exposed to air, effectively preventing further oxidation. The strongest aluminium alloys are less corrosion resistant due to galvanic reactions with alloyed copper.

Aluminium is one of the few metals that retain full silvery reflectance in finely powdered form, making it an important component of silver paints. Aluminium mirror finish has the highest reflectance of any metal in the 200–400 nm and the 3000–10000 nm (far IR) regions, while in the 400–700 nm visible range it is slightly outdone by tin and silver and in the 700–3000 by silver, gold, and copper.

Aluminium is a good thermal and electrical conductor, by weight better than copper. Aluminium is capable of being a superconductor, with a superconducting critical temperature of 1.2 kelvins and a critical magnetic field of about 100 gauss.

Although aluminium is the most abundant metallic element in the Earth's crust (believed to be 7.5 to 8.1 percent), it is rare in its free form, occurring in oxygen-deficient environments such as volcanic mud, and it was once considered a precious metal more valuable than gold. Napoleon III, emperor of France, is reputed to have given a banquet where the most honoured guests were given aluminium utensils, while the other guests had to make do with gold.[7][8] The Washington Monument was completed, with the 100 ounce (2.8 kg) aluminium capstone being put in place on December 6, 1884, in an elaborate dedication ceremony. It was the largest single piece of aluminium cast at the time. At that time, aluminium was more expensive than silver, gold, or platinum. Aluminium has been produced in commercial quantities for just over 100 years.

Aluminium is a strongly reactive metal that forms a high-energy chemical bond with oxygen. Compared to most other metals, it is difficult to extract from ore, such as bauxite, due to the energy required to reduce aluminium oxide (Al2O3). For example, direct reduction with carbon, as is used to produce iron, is not chemically possible, since aluminium is a stronger reducing agent than carbon. Aluminium oxide has a melting point of about 2,000 °C. Therefore, it must be extracted by electrolysis. In this process, the aluminium oxide is dissolved in molten cryolite and then reduced to the pure metal. The operational temperature of the reduction cells is around 950 to 980 °C. Cryolite is found as a mineral in Greenland, but in industrial use it has been replaced by a synthetic substance. Cryolite is a chemical compound of aluminium, sodium, and calcium fluorides: (Na3AlF6). The aluminium oxide (a white powder) is obtained by refining bauxite in the Bayer process of Karl Bayer. (Previously, the Deville process was the predominant refining technology.)

http://en.wikipedia.org/wiki/Aluminium

i have chosen aluminium because it is a non-corrosive sheet metal which is quite malleuable and it is inexpensive. this is a excellent choice of material for a outdoor solar garden light

material research arcrylic

Acrylic is a rigid plastic with a high degree of transparency. It is resistant to inorganic acids and alkalis but is attacked by a wide range of organic solvents. Acrylic's clarity and stability make it very suitable for the manufacture of burets and in sheet form it may be cemented to produce tanks, trays, racks etc. Acrylic may be used at temperatures up to 70°C continuously and to 90°C for short periods. 10mm thick Acrylic provides an effective barrier for Beta Radiation Protection. Dynalab Corp's acrylic fabrication shop fabricates thousands of catalog and custom acrylic products.

Excellent resistance (no attack) to Mineral Oils.

Good resistance (minor attack) to Dilute Acids, Aldehydes and Aliphatic Hydrocarbons.

Limited resistance (moderate attack and suitable for short term use only) to Bases.

Poor resistance Poor resistance (not recommended for use) with Concentrated Acids, Alcohols, Esters, Aromatic and Halogenated Hydrocarbons, Ketones, Vegetable Oils and Oxidizing.

Nearly crystal clear, Acrylic is an excellent choice for display cases, vitrines, and point of purchase items.

Thicker Acrylic material can shield against beta radiation.

Available in a wide array of forms and colors.

Machineable and heat-bendable.

Acrylic can be solvent bonded.

Extruded acrylic can be flame polished to obtain a glass-like finish.

Applications include aquariums, picture frames, shelves, and cabinets.

Maximum Temperature: 194°F 90°C
Minimum Temperature: -76°F -60°C

Autoclavable: No

Melting Point: 212°F 100°C
Tensile Strength: 7,000 psi

Hardness: R120

UV Resistance: Good
Clear
Rigid

Specific Gravity: 1.18

http://www.dynalabcorp.com/technical_info_acrylic.asp

i have chosen to research this material as it is a plastic that i can use for the light output that has a high level of transperancy. it has a melting point at 100 degrees celcius and it comes in sheets

my first prototype

these are some photos for the prototype that i am making right now. this prototype light is made from sheet aluminum and it is cut in a computer aided machine (CAM) machine. the sheet that looks like a plus folds into a box while the other more complicated looking sheet is the bottom of the light once folded. the box will be riveted using brackets and the bottom of the box will have small screws so the bottom plate can come off if the battery needs to be replaced after time.

week 3 term 2

on tuesday, we all did materials research and on wednesday, we blogged. on friday, we are going to be doing some practical work on our prototypes

bottom and top plate for prototype

this is the bottom plate that has been drawn on the computer. i can cut this shape out directly from the computer using the cam machine (computer aided machine). the cam machine is designed to engrave or cut out sheet metals, sheet plastics, etch pcb boards etc.

week 2 term 2

this week, i have done a 18242 sheet. after that, i started taking apart a solar garden light. we will name what the components will do. on friday, we are blogging and mabye doing some practical

solar garden lamp

after the 18242 sheet was completed, i have started pulling a shop-bought solar garden lamp apart to get out the circuit and its components. i am doing this because i am making a small aliminium solar powered lamp using the circuit that i got from the solar garden lamp. this circuit uses the transistor oscilator circuit to convert the voltage form 1.2V to 3V. my aliminium light will be in the shape of a small box and there will be 2 led's alongside the solar panel. this light will be my first prototype

week 1 term 2

i have had a holiday break and it was 2 weeks long. cool. this week i have pulled apart a solar garden light. i am going to use the parts inside to make a prototype light. we are also doing some more designing on our final design