ELECTRIC SECURITY FENCE WIRING.

WHY ELECTRIC FENCING FOR SECURITY?
Deter, Detect and Delay
A high-voltage shock combined with a physical barrier will deter anyone from attempting to penetrate the perimeter fence.
The detecting ability of an electric fence energizer will sound an alarm when the perimeter of the property being
protected has been infiltrated or tampered with.
By keeping the perimeter protected using an electric fence, the attempted break in of the protected area is delayed, giving
additional time for a reaction team to respond.

The cost-effective, reliable and effective designs have been the focus over the past twenty years. A dynamic design team develops new and existing products to better secure your family and
friends. The continually evolving range offers innovative solutions for many residential applications, with many choices to ensure that the right product is available to make homes secure
without compromising on aesthetics. The large range of wall top brackets and posts have made it
easy to secure most walls offering a range of effective security

Office and commercial parks,car and boat showrooms and yards, caravan and motor home displays and outdoor showrooms have not been ignored by criminals and are often also a soft target for vandals.Have identified this need for secure perimeter protection combined with aesthetically
pleasing designs that do not compromise on the effectiveness of the security. Modulus brackets
and post systems are just some of the trusted solutions where the security electric fencing
products look good yet work effectively.

Traditionally electric fence energizers for animal farming control did not have a fence monitor to
detect a break in the fence.
The detecting feature has become an integral part of game and animal control. It allows the user
to monitor the condition of the fence at the energizer without having to patrol the fence regularly,
thus saving time and money.
Poaching of game is an additional problem faced by game reserves and game farms, but the security
features offered by the electric fencing energizers can assist in this battle.

Products.(ENERGIZERS)

The Wizord 2 or 4 is the logical choice for domestic and light industrial installations where a medium-powered energizer is required. This generation of energizers has been field tested for many years and boasts unsurpassed reliability. Simple to install and easy to maintain. FEATURES • High voltage monitor will alarm when the live wires are tampered with • Earth wire monitor will alarm when the earth wires are tampered with • Easy-to-use tag switch for controlling the unit • Connectable to an armed response radio or GSM module • Gate monitor input monitors the position of the gate to indicate if the gate is open • Lightning and power surge suppression built in to reduce the possibility of damage due to power surges • Battery backup system in case of power failure • Intelligent power saving to extend the battery life and save energy • Siren and strobe outputs to indicate fence condition

WARNING DEVICES
 Sirens • Available in 15 and 30 watt power output • 12 volt DC supply

FENCELIGHT • Install it on your electric fence to indicate power status for peace of mind • One directional viewing angle, allowing the light to shine into the secure area only. The status is not visible to external areas • Working voltage between 3 kV and 12 kV approximately • Dual stage design allows the intensity on the light to increase as the voltage on the fence increases, giving a better indication of how much voltage is on the fence • Can be installed between any earth and live wires • Can be used with most electric fence energizers Warning signs • UV protected for long life • Wire clips on the warning sign reduce installation time • Compliance requirements, every 10m and change of direction • IEC 60335-2-76 compliant • Custom-made version available to order.


TIPS TO INCREASE YOUR SECURITY.

• Spacing between fence wires must not exceed 100mm. This will reduce attempts to part wires. Earth or live loops fitted on the fence will cause an alarm when there is an attempt to part the wire. • The bottom fence wire where possible should be live and fitted with an anti lift loop where there is a threat of lifting this bottom wire. The top wire must also be live. • All electric fencing live wires must be connected in a series circuit so that a cut live wire can be detected anywhere along the fence. • Spacing between posts must not exceed 3 metres. This will discourage attempts to part wires. In the case of freestanding fencing it is recommended that a shorter post be placed between the main posts reducing the span to 1.5m. This in-between shorter post will stop any attempts to lift the bottom wires. Ensure that the ground under the freestanding fencing is secure and not easy to dig under. The height of the freestanding fence must be at least 2m. • The height of the bracket above the wall is important, the higher the wall brackets the more it discourages attempts to step over the fence. The wider walls will need higher and angled brackets to cover the span of the wall top and reduce any chance of standing on the wall. • The fence wires must be under constant tension using compression springs. This will improve the aesthetics and the security of the fence. • Alarm zones lengths should not be longer than 200 metres. The zones must be powered by independent energizer zones. This will help locate the fault faster. This is not always possible due to cost and location constraints. In high security areas shorter zones are recommended. • No two zones must rely on each other being intact to operate effectively and must be independently alarm monitored. This is important in the case of an attempted multi-point entry breach of the fence. • Gates can be a weak point. Make sure that sliding gates cannot be lifted up off the rack and be slid open. In the case of swing gates they can be forced open when they are closed. These gates can be monitored for unauthorised entry using a magnetic switch. • Ensure that the fence is kept free of vegetation. Frequent testing of the fence is imperative. This test must be on a few points along the fence line.

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AUTOMATED SECURITY SOLUTIONS IN NIGERIA.

In today’s world of socioeconomic and security realities, it is not out of place to think that
governance, business and corporate organizations require a well-coordinated and result-oriented
security blueprint that is not only state-of-the-art surveillance solutions compliance but also readily
and easily executable.
At this very crucial moment in the annals of our country, we feel compelled by the doctrines of
necessity and corporate social responsibility to be part of a solution body to the emerging security
challenge that is almost overwhelming the entire fabrics of the nation. We therefore offer our
expertise, competence and experience to your esteem organization (Colby Systems) in her quest
towards securing and maintaining a peaceful and safe working environment amongst her staff and
the public.
 
     Our approach to issues of security is holistic and automation driven.
Because of its complex nature, we view and address security as a full complement and not in parts
as many of us have done over the years. This total approach is in line with contemporary security
approaches in developed countries of the world. And this explains why we have come to the
conclusion that efficient and proactive preventive measures design will not only manage the
situation but will certainly drastically minimize our collective exposure to these attendant risks. To
this end, we have classified all threats in a simple outline to enable us appreciate the relevant
solution for each environment:
 VEHICULAR ENTRANCE PROTECTION
 PEDESTRIAN GATE ENTRANCE PROTECTION
 FACILTY ENTRANCE PROTECTION
 PERIMETER PROTECTION
Each of these headlines have peculiar and specific tools designed to meet its needs.We provide quality delivery and training on product knowledge through technical collaboration with our foreign partners among which are CEIA,
ADANI SYSTEMS, ATG ACCESS, ASTROPHYSICS INC, TONALI SpA, DITEC, BRIJOT
MICROSEMI, COMETA, JVC, PANASONIC, OZAK, PAXTON, ROSSLARE,ONITYWAVESIGHT,
SAIMA etc. We deliver, install and further provide consultancy services, particularly training on the
use and deployment of these devices.

OUR SERVICES:
Engineering services.
System & product procurement, and installation services.
After sales services: Technical support and maintenance.
Consultancy and project preparation services.

SLIDING DOORS.
Volo - Onda
Curved sliding doors.
Nowadays, designing buildings with technological frontages is becoming
increasingly more popular. Naturally, the quality and look of automatic doors
must be adapted to blend it perfectly with technological buildings.
Volo is a new, reduced height DITEC automation for curved automatic sliding
doors, specially designed to meet recent architectural requirements.
With Volo and Onda, architects and designers can make “ad hoc” designs of
revolving and curved automatic doors, to ensure they are effectively integrated
with existing buildings.
The appeal of a curved door, combined with the quiet and smooth operation
of DITEC automations enhance the look and importance
of the entrance. Hotels, restaurants, companies and high class buildings are
the ideal applications of these top quality entrances.

DITEC leads the way in these practical and useful automations. An automatic door is also an ideal tool to solve
issues concerning architectural barriers. DITEC confirms its ongoing commitment and solid business by
providing new solutions and a full range of products in order to meet any requirements.
Types of Straight Sliding Door.
1. Rex
For straight sliding doors.
Max. capacity with 1 wing: 100 kg,
with 2 wings: 140 kg.
Gear motor complete with encoder and microprocessor based
electronic control panel.
Anodised aluminium pro_le section runner.
Operated by means of an electrically conductive synthetic drive belt.
Duty class: 5, very heavy.
Version with “ standard ” Plug & Play control panel, opening speed 1m/s.
Version V with “ superior ” control panel,
opening speed 1.2 m/s, adjustable.
2. Valor
For straight sliding doors.
Max. capacity with 1 wing: 300 kg,
with 2 wings: 360 kg.
VALOR L - up to 180 kg (2 wings) - duty class 5 very heavy - 1 million cycles
VALOR P - up to 220 kg (2 wings) - duty class 5 very heavy - 1 million cycles
VALOR N - up to 240 kg (2 wings) or 300 kg (2 wings) with reinforced wheels
duty class - 6 continuons - 3 million cycles
VALOR HS - up to 300 kg (2 wings) or 360 kg (2 wings) with the addition
of a 2nd whell kit duty class - 5 very heavy - 1 million cycles
VALOR T - for telescopic sliding doors - up to 260 kg (4 wing)
duty class 5 very heavy - 1 million cycles
3. Ten
For straight sliding doors.
Automation casing height: 10 cm only.
Max. capacity with 1 wing: 120 kg,
with 2 wings: 200 kg.
Gear motor complete with encoder and microprocessor based
electronic control panel.
Anodised aluminium extruded pro_le section runner.
Compact, extruded aluminium casing, consisting of two separate, horizontally
extended with slot-in _tting, measuring only 100 mm in height, with long vertical
adjustment (can be extended up to 15 mm).
Duty class 5, very heavy. Opening speed 1.6 m/s.

Pam
Control Systems for Frames
Control systems for frames specially developed to better satisfy the requirements of automatic pedestrian
entrances. The wide range of solutions offered allows DITEC frames to perfectly blend in with any architectural
environment by smartly and seamlessly inserting the entrance, whilst complying with the strictest standards
applicable.
In a nutshell, the main benefits ensured by DITEC entrances are their practicality, safety, smart look, access
control and air conditioning control.
Profiles and seals.
They allow complete “automatic sliding doors” to be manufactured, which can be tailored to specific
requirements.
Effective temperature and sound control.
Antipanic break-out ASMI/ASME system and antipanic f

CCTV SURVEILLANCE SYSTEM
For wireless perimeter Surveillance, simplified and effective facility monitoring system like Factory, Plant,
Terminals or Projects lose lots of money by theft, damages, productivity, discipline, but this could be
prevented with the installation of our cost effective electronic security and intelligence surveillance systems. We understand the security needs of Large Business.
The most effective use of security cameras are for the purposes of viewing and recording key events in many
different locations throughout the Office Premises, homes, Government premises, City Surveillance AND
Terminals generally. They can be placed in high-traffic areas both inside and outside the building or location.
They can also be placed at all entrances into the buildings and City and high prone security areas within the city,
parking lot and ground for monitoring.
A network dome camera with endless 360° pan operation and 36 x optical zoom’s 1/4 inch progressive scan
CCD sensor with infrared cut filter delivers high quality images with good colour reproduction during daylight
hours. During periods of low-light or at night the camera will automatically remove the IR cut filter and switch
to black and white video sensitive to infrared illumination. The camera’s advanced pan-tilt-zo

Schedule

om (PTZ) direct
drive motor provides fast movement speeds of up to 400 degrees/sec as well as highly precise control for
following moving targets accurately. Like all network cameras, these range has an integrated web server and can
be viewed over a Local Area Network (LAN), Wide Area Network (WAN) or via the Internet as a streaming IP
webcam, it can be indoor or outdoor.


BENEFITS OF CCTV:
1. CCTV helps prevent crime simply by imprinting in the mind of everyone that they are being watched.
2. CCTV is able to inspire confidence, because it creates a safe feeling environment.
3. CCTV prevents theft and pilferage and waste . The more employees and customers know they are being watched, the
less likely they want to engage in any act of theft or wastage.
4. CCTV afford you a real time view of your entire facility and thus increase productivity because employees are aware
and they keep the momentum of work on with less time for frivolities.
5. It increases safety of the work environment because each person becomes concious and cautious.
6. CCTV protect employees. More often than not, employees are vulnerable to either physical or verbal attacks from the
public. Often, in stressful situations, customers may lash out at a company representative. If the employee knows
they are being watched by CCTV camera, he or she will try to minimize these cases and stay calmly deal. Moreover, it
is able to protect the employees against false allegations that might be common in some areas of business.
7. CCTV Video surveillance, monitoring and recording will improve the health of any business.
8. ……. And many more.

WAVESIGHT RADIOS
Wavesight indoor/outdoor wireless CCTV solutions offer a genuine alternative to cable or fibre connections
between camera or remote NVR/DVR and control room. Using standards based OFDM technology with
proprietary security features operating on license exempt frequency bands, Wavesight wireless links and
networks can be deployed rapidly and provide extremely low latency, high quality video ideally suited to modern
security and surveillance installations.
Wavesight is also able to specify and supply alternative wireless technologies operating in the licensed frequency
spectrum, where long term contention is a concern, or exceeding the 1Gbps bandwidth barrier is a must. In all
networking environments interconnects matter and this is no exception in the deployment of a wireless
infrastructure. Wavesight has carefully selected a group of ‘best of breed’ technology products to help our
partners deliver an end to end solution. Wavesight is the complete partner you can trust, where customer service
is key and no challenge is too big or too small.
 High quality video
 Extremely low latency
 Cost effective alternative to cable or leased line fiber
 High performance, video optimized operation
 Encrypted data communications
 Rapid deployment
 Easy installation
 Licensed and licensed exempt radio solutions
 Complete structured infrastructure design and deployment
 Single point base station / satellite
 Integrated vertically polarized antenna, 14dBi, 40°
 Up to 1km operating range
 Up to 54Mbps data rate
 IP65 construction
 1W EIRP power output
 48VDC POE (802.3af)
 Extremely compact and light (10cm x 12cm x 5cm, 0.3Kg)

TO BE CONTINUED....

Aluminium works.

Aluminium Partitions

 These aluminium partitions are designed and fabricated using the modern patterns and are known for the durability and spectacular finish.

                         

Aluminum Glass Partition

This Aluminum Glass Partition is used to make a group or cellular partitions within the specific area, which are mostly used in both residential and commercial purpose that helps to divide the cabins of employees. We manufacture this aluminum partition with glass using high grade material of aluminum and glass, procured from our well known vendors of the industry. These are widely appreciated for their designer look, attractive designs, exclusive patterns, durability, sturdy construction and cost effective rate. These aluminum partitions with glass are offered to our customers at industry leading prices.

Aluminium Door Frames

We offer a wide range of aluminium door frame used for supporting various doors made of premium aluminum. Available in various specifications these aluminium door frames are featured with durability, corrosion resistant and less maintenance. Also available in various colors these aluminum door frames frames can be customized as the clients specifies.  All this aluminum fabrication work not only enhances the look and feel of the establishments and offices but also create a clean atmosphere.

ALUMINIUM DOOR
Traditional doors, made out of aluminium frames with glass aur laminateboard panes inside and floor spring mounted engineered to realize the architect’s vision Along with these doors fixed and framed glazings leaves a great impact and unique look. 

Aluminium Work

Our clients can avail from us a comprehensive range of Aluminum Sheet Metal. These sheets come in plethora of sizes and thicknesses. The sheet that we offer can be easily drilled, machined, sheared and fitted. Industrial valves, industrial fittings and general screw machines can be manufactured using these metals. Our sheets are also applicable in the metal service centers. The sheets can be made in requisite shapes for our clients. Different aluminum works that we offer:

Aluminium Sliding Window

We offer our clients Aluminum Sliding Window. These windows come in variegated colors, sizes and shapes. Our windows are fabricated using premium quality material and hence impart an elegant look to any structure. Finished to excellence, these windows are easy to operate and provide a durable life span. These windows can be developed in customized sizes also.  

Aluminum Partition Work

We offer our clients Aluminum Partition Work. The partitions that we fabricate are made using genuine aluminum. Moreover, these partitions are easy install, rugged in construction and impart elegance. As per the sizes and shapes details provided, customized partitions can be developed. 

SLIDING DOOR
Aluminium windows with flexibility of opening by sliding a shutter according to requirement. The unique feature of this type of windows is that, these do not require any space for opening moreover the window panels moves parallel to walls.

                                     

                                                         

CASEMENT WINDOWS                                                   
Aluminium casement windows are quit elegant and convenient and are used extensively in residential buildings. The hinged panels enables windows to open either side. These can also be made to have mosquito mesh, grills etc.

SECURITY FENCED BARBED WIRE.

Razor barbed wire fencing and razor wire concertina makes the majority of our products. Razor barbed wire fencing is usually made of galvanized steel blade or stainless steel blade. Two pieces of stainless steel razor wire or zinc-coated razor wire can be bounded together by clips to make it stronger. The spiral intersecting barbed wire presents an intersecting shape after opening with beautiful outlook and practical property.
Material for Razor Barbed Wire Fencing: Galvanized blade, stainless steel blade.
Features: Compact and rational structure, high safety factor, for the protection of prison and key project.

Technical Note: Razor barbed wire fencing can be made according to the actual dimension of customer; the special specification is manufactured according to the drawing.

In order to install a razor concertina fencing needs razor barbed wire and other items. There is a fencing example:

• Concertina Barbed Wire: 750mm Dia.
• Barbed Wire
• Fabric: 3.76/4.88mm, 3m high, mesh 50mm × 50mm coated.
• Brace Rail Pipe; 89.9mm, 4m high length coated epoxy green.
• Line post: hollow section 100 × 100 × 4 × 3000mm with base Plate and top Cover (post cap) coated.
• Double arm 50 × 50 × 5mm each 500mm long with 6 notches (epoxy angle plated).
• Tie Wire: 2.5mm/3.76 PVC Coated.
• Base Plate 300 × 300 × 6mm with Epoxy Paint Finish.
• Slats

Mobile Security Barriers（ Rapid Deployment of High Density Razor Wire）
1. The system is designed to provide rapid protection - the 75-1000 meter barriers of barbed tape/razor wire coils can be deployed in seconds. 2. Barriers are fully re-usable. 3. Equipment is supplied to uplift and recompress the barrier into modules, simple to handle and compact to store. 4. A single carrier unit can be quickly refilled to drop many miles of barrier in a short space of time. 5. Systems can be tailored to meet customers exact requirements. 6. No Police or Military Organization can afford to be without this valuable tool.

Razor Wire
Outside Diameter	No.of Loops	Standard Length per Coil	Type	Notes
450mm	33	8M	CBT-65	Single coil
500mm	41	10M	CBT-65	Single coil
700mm	41	10M	CBT-65	Single coil
960mm	53	13M	CBT-65	Single coil
500mm	102	16M	BTO-10.15.22	Cross type
600mm	86	14M	BTO-10.15.22	Cross type
700mm	72	12M	BTO-10.15.22	Cross type
800mm	64	10M	BTO-10.15.22	Cross type
960mm	52	9M	BTO-10.15.22	Cross type

Good Quotations by Famous People:

"Moral indignation is jealousy with a halo."

- H. G. Wells (1866-1946)

"Glory is fleeting, but obscurity is forever."

- Napoleon Bonaparte (1769-1821)

"The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts."

- Bertrand Russell (1872-1970)

"Victory goes to the player who makes the next-to-last mistake."

- Chessmaster Savielly Grigorievitch Tartakower (1887-1956)

"Don't be so humble - you are not that great."

- Golda Meir (1898-1978) to a visiting diplomat

"His ignorance is encyclopedic"

- Abba Eban (1915-2002)

"If a man does his best, what else is there?"

- General George S. Patton (1885-1945)

"Political correctness is tyranny with manners."

- Charlton Heston (1924-2008)

"You can avoid reality, but you cannot avoid the consequences of avoiding reality."

- Ayn Rand (1905-1982)

"When one person suffers from a delusion it is called insanity; when many people suffer from a delusion it is called religion."

- Robert Pirsig (1948-)

"Sex and religion are closer to each other than either might prefer."

- Saint Thomas More (1478-1535)

"I can write better than anybody who can write faster, and I can write faster than anybody who can write better."

- A. J. Liebling (1904-1963)

"People demand freedom of speech to make up for the freedom of thought which they avoid."

- Soren Aabye Kierkegaard (1813-1855)

"Give me chastity and continence, but not yet."

- Saint Augustine (354-430)

"Not everything that can be counted counts, and not everything that counts can be counted."

- Albert Einstein (1879-1955)

"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."

- Albert Einstein (1879-1955)

"A lie gets halfway around the world before the truth has a chance to get its pants on."

- Sir Winston Churchill (1874-1965)

"You may not be interested in war, but war is interested in you."

- Leon Trotsky (1879-1940)

Always do your best. What you plant now, you will harvest later.

Og Mandino

Read more at http://www.brainyquote.com/quotes/quotes/o/ogmandino164003.html#RFhREYeLUrpoKrT8.99

Aluminium;WIKIPEDIA

Aluminium
13Al
B ↑ Al ↓ Ga magnesium ← aluminium → silicon
Aluminium in the periodic table
Appearance
silvery gray metallic Spectral lines of aluminium
General properties
Name, symbol,number	aluminium, Al, 13
Pronunciation	UK i/ˌæljʉˈmɪniəm/ al-ew-min-ee-əm; US i/əˈljuːmɨnəm/ ə-lew-mi-nəm
Element category	poor metal
Group, period,block	13, 3, p
Standard atomic weight	26.9815386(13)
Electron configuration	[Ne] 3s2 3p1 2, 8, 3
History
Prediction	Antoine Lavoisier[1] (1787)
First isolation	Friedrich Wöhler[1] (1827)
Named by	Humphry Davy[1] (1807)
Physical properties
Phase	solid
Density(near r.t.)	2.70 g·cm−3
Liquid density atm.p.	2.375 g·cm−3
Melting point	933.47 K, 660.32 °C, 1220.58 °F
Boiling point	2792 K, 2519 °C, 4566 °F
Heat of fusion	10.71 kJ·mol−1
Heat of vaporization	294.0 kJ·mol−1
Molar heat capacity	24.200 J·mol−1·K−1
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 1482 1632 1817 2054 2364 2790
Atomic properties
Oxidation states	3, 2[2], 1[3] (amphoteric oxide)
Electronegativity	1.61 (Pauling scale)
Ionization energies (more)	1st: 577.5 kJ·mol−1
	2nd: 1816.7 kJ·mol−1
	3rd: 2744.8 kJ·mol−1
Atomic radius	143 pm
Covalent radius	121±4 pm
Van der Waals radius	184 pm
Miscellanea
Crystal structure	face-centered cubic
Magnetic ordering	paramagnetic[4]
Electrical resistivity	(20 °C) 28.2 nΩ·m
Thermal conductivity	237 W·m−1·K−1
Thermal expansion	(25 °C) 23.1 µm·m−1·K−1
Speed of sound(thin rod)	(r.t.) (rolled) 5,000 m·s−1
Young's modulus	70 GPa
Shear modulus	26 GPa
Bulk modulus	76 GPa
Poisson ratio	0.35
Mohs hardness	2.75
Vickers hardness	167 MPa
Brinell hardness	245 MPa
CAS registry number	7429-90-5
Most stable isotopes
Main article: Isotopes of aluminium
iso NA half-life DM DE (MeV) DP 26Al trace 7.17×105 y β+ 1.17 26Mg ε - 26Mg γ 1.8086 - 27Al 100% 27Al is stable with 14 neutrons
v   t   e   · ref

Aluminium (or aluminum) is a chemical element in the boron group with symbol Aland atomic number 13. It is a silvery white, soft, ductile metal. Aluminium is the third most abundant element (after oxygen and silicon), and the most abundant metal, in theEarth's crust. It makes up about 8% by weight of the Earth's solid surface. Aluminium metal is so chemically reactive that native specimens are rare and limited to extremereducing environments. Instead, it is found combined in over 270 different minerals.^[5] The chief ore of aluminium is bauxite.

Aluminium is remarkable for the metal's low density and for its ability to resist corrosiondue to the phenomenon of passivation. Structural components made from aluminium and its alloys are vital to the aerospace industry and are important in other areas oftransportation and structural materials. The most useful compounds of aluminium, at least on a weight basis, are the oxides and sulfates.

Despite its prevalence in the environment, aluminium salts are not known to be used by any form of life. In keeping with its pervasiveness, aluminium is well tolerated by plants and animals.^[6] Owing to their prevalence, potential beneficial (or otherwise) biological roles of aluminium compounds are of continuing interest.

• • • 
      

Characteristics

Etched surface from a high purity (99.9998%) aluminium bar, size 55×37 mm

Physical

Aluminium is a relatively soft, durable, lightweight, ductile and malleable metal with appearance ranging from silvery to dull gray, depending on the surface roughness. It is nonmagnetic and does not easily ignite. A fresh film of aluminium serves as a good reflector (approximately 92%) of visible lightand an excellent reflector (as much as 98%) of medium and far infrared radiation. The yield strength of pure aluminium is 7–11 MPa, while aluminium alloys have yield strengths ranging from 200 MPa to 600 MPa.^[7]Aluminium has about one-third the density and stiffness of steel. It is easily machined,cast, drawn and extruded.

Aluminium atoms are arranged in a face-centered cubic (fcc) structure. Aluminium has astacking-fault energy of approximately 200 mJ/m².^[8]

Aluminium is a good thermal and electrical conductor, having 59% the conductivity of copper, both thermal and electrical, while having only 30% of copper's density. Aluminium is capable of being a superconductor, with a superconducting critical temperature of 1.2 Kelvin and a critical magnetic field of about 100 gauss (10milliteslas).^[9]

Chemical

Corrosion resistance can be 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.^[7] This corrosion resistance is also often greatly reduced by aqueous salts, particularly in the presence of dissimilar metals.

Owing to its resistance to corrosion, aluminium is one of the few metals that retain silvery reflectance in finely powdered form, making it an important component of silver-colored paints. Aluminium mirror finish has the highest reflectance of any metal in the 200–400 nm (UV) and the 3,000–10,000 nm (far IR) regions; in the 400–700 nm visible range it is slightly outperformed by tin and silver and in the 700–3000 (near IR) by silver,gold, and copper.^[10]

Aluminium is oxidized by water to produce hydrogen and heat:

2 Al + 3 H₂O → Al₂O₃ + 3 H₂

This conversion is of interest for the production of hydrogen. Challenges include circumventing the formed oxide layer which inhibits the reaction and the expenses associated with the storage of energy by regeneration of the Al metal.^[11]

Isotopes

Main article: Isotopes of aluminium

Aluminium has many known isotopes, whose mass numbers range from 21 to 42; however, only ²⁷Al (stable isotope) and ²⁶Al (radioactive isotope, t_1/2 = 7.2×10⁵ y) occur naturally. ²⁷Al has a natural abundance above 99.9%. ²⁶Al is produced from argon in theatmosphere by spallation caused by cosmic-ray protons. Aluminium isotopes have found practical application in dating marine sediments, manganese nodules, glacial ice, quartzin rock exposures, and meteorites. The ratio of ²⁶Al to ¹⁰Be has been used to study the role of transport, deposition, sediment storage, burial times, and erosion on 10⁵ to 10⁶year time scales.^[12] Cosmogenic ²⁶Al was first applied in studies of the Moon and meteorites. Meteoroid fragments, after departure from their parent bodies, are exposed to intense cosmic-ray bombardment during their travel through space, causing substantial²⁶Al production. After falling to Earth, atmospheric shielding drastically reduces ²⁶Al production, and its decay can then be used to determine the meteorite's terrestrial age. Meteorite research has also shown that ²⁶Al was relatively abundant at the time of formation of our planetary system. Most meteorite scientists believe that the energy released by the decay of ²⁶Al was responsible for the melting and differentiation of someasteroids after their formation 4.55 billion years ago.^[13]

Production and refinement

See also: Category:Aluminium minerals and List of countries by aluminium production

Bauxite, a major aluminium ore. The red-brown colour is due to the presence of ironminerals.

Aluminium forms strong chemical bonds with oxygen. Compared to most other metals, it is difficult to extract from ore, such as bauxite, due to the high reactivity of aluminium and the high melting point of most of its ores. For example, direct reduction with carbon, as is used to produce iron, is not chemically possible because aluminium is a stronger reducing agent than carbon. Indirect carbothermic reduction can be carried out using carbon and Al₂O₃, which forms an intermediate Al₄C₃ and this can further yield aluminium metal at a temperature of 1900–2000 °C. This process is still under development; it requires less energy and yields less CO₂ than the Hall-Héroult process, the major industrial process for aluminium extraction.^[19] Electrolytic smelting of alumina was originally cost-prohibitive in part because of the high melting point of alumina, or aluminium oxide, (about 2,000 °C(3,600 °F)). Many minerals, however, will dissolve into a second already molten mineral, even if the temperature of the melt is significantly lower than the melting point of the first mineral. Molten cryolite was discovered to dissolve alumina at temperatures significantly lower than the melting point of pure alumina without interfering in the smelting process. In the Hall-Héroult process, alumina is first dissolved into molten cryolite with calcium fluoride and then electrolytically reduced to aluminium at a temperature between 950 and 980 °C (1,740 to 1,800 °F). Cryolite is a chemical compound of aluminium and sodium fluorides: (Na₃AlF₆). Although cryolite is found as a mineral in Greenland, its synthetic form is used in the industry. The aluminium oxide itself is obtained by refining bauxite in the Bayer process.

The electrolytic process replaced the Wöhler process, which involved the reduction of anhydrous aluminium chloride with potassium. Both of the electrodes used in the electrolysis of aluminium oxide are carbon. Once the refined alumina is dissolved in the electrolyte, it disassociates and its ions are free to move around. The reaction at the cathode is:

Al³⁺ + 3 e⁻ → Al

Here the aluminium ion is being reduced. The aluminium metal then sinks to the bottom and is tapped off, usually cast into large blocks called aluminium billets for further processing.

At the anode, oxygen is formed:

2 O²⁻ → O₂ + 4 e⁻

To some extent, the carbon anode is consumed by subsequent reaction with oxygen to form carbon dioxide. The anodes in a reduction cell must therefore be replaced regularly, since they are consumed in the process. The cathodes do erode, mainly due to electrochemical processes and metal movement. After five to ten years, depending on the current used in the electrolysis, a cell has to be rebuilt because of cathode wear.

World production trend of aluminium

Aluminium electrolysis with the Hall-Héroult process consumes a lot of energy, but alternative processes were always found to be less viable economically and/or ecologically. The worldwide average specific energy consumption is approximately 15±0.5 kilowatt-hoursper kilogram of aluminium produced (52 to 56 MJ/kg). The most modern smelters achieve approximately 12.8 kW·h/kg (46.1 MJ/kg). (Compare this to the heat of reaction, 31 MJ/kg, and the Gibbs free energy of reaction, 29 MJ/kg.) Reduction line currents for older technologies are typically 100 to 200 kiloamperes; state-of-the-art smelters operate at about 350 kA. Trials have been reported with 500 kA cells.^{[citation needed]}

The Hall-Heroult process produces aluminium with a purity of above 99%. Further purification can be done by the Hoope process. The process involves the electrolysis of molten aluminium with a sodium, barium and aluminium fluoride electrolyte. The resulting aluminium has a purity of 99.99%.^[20][21]

Electric power represents about 20% to 40% of the cost of producing aluminium, depending on the location of the smelter. Aluminium production consumes roughly 5% of electricity generated in the U.S.^[22] Smelters tend to be situated where electric power is both plentiful and inexpensive, such as the United Arab Emirates with excess natural gas supplies and Iceland and Norway with energy generated from renewable sources. The world's largest smelters of alumina are People's Republic of China, Russia, and Quebec andBritish Columbia in Canada.^[22][23][24]

Aluminium spot price 1987 2012

In 2005, the People's Republic of China was the top producer of aluminium with almost a one-fifth world share, followed by Russia, Canada, and the USA, reports the British Geological Survey.

Over the last 50 years, Australia has become a major producer of bauxite ore and a major producer and exporter of alumina (before being overtaken by China in 2007).^[23][25] Australia produced 68 million tonnes of bauxite in 2010. The Australian deposits have some refining problems, some being high in silica, but have the advantage of being shallow and relatively easy to mine.^[26]

Applications

General use

Aluminium is the most widely used non-ferrous metal.^[37] Global production of aluminium in 2005 was 31.9 million tonnes. It exceeded that of any other metal except iron (837.5 million tonnes).^[38] Forecast for 2012 is 42–45 million tonnes, driven by rising Chinese output.^[39]

Aluminium is almost always alloyed, which markedly improves its mechanical properties, especially when tempered. For example, the common aluminium foils and beverage cans are alloys of 92% to 99% aluminium.^[40] The main alloying agents are copper, zinc,magnesium, manganese, and silicon (e.g., duralumin) and the levels of these other metals are in the range of a few percent by weight.^[41]

Household aluminium foil

Aluminium-bodied Austin "A40 Sports"(c. 1951)

Aluminium slabs being transported from a smelter

Some of the many uses for aluminium metal are in:

• Transportation (automobiles, aircraft, trucks, railway cars, marine vessels, bicycles, etc.) as sheet, tube, castings, etc.
• Packaging (cans, foil, frame of etc.)
• Construction (windows, doors, siding, building wire, etc.).^[42]
• A wide range of household items, from cooking utensils to baseball bats, watches.^[43]
• Street lighting poles, sailing ship masts, walking poles, etc.
• Outer shells of consumer electronics, also cases for equipment e.g. photographic equipment, MacBook Pro's casing
• Electrical transmission lines for power distribution
• MKM steel and Alnico magnets
• Super purity aluminium (SPA, 99.980% to 99.999% Al), used in electronics and CDs.
• Heat sinks for electronic appliances such as transistors and CPUs.
• Substrate material of metal-core copper clad laminates used in high brightness LED lighting.
• Powdered aluminium is used in paint, and in pyrotechnics such as solid rocket fuels andthermite.
• Aluminium can be reacted with hydrochloric acid or with sodium hydroxide to produce hydrogen gas.
• A variety of countries, including France, Italy, Poland, Finland, Romania, Israel, and the former Yugoslavia, have issued coins struck in aluminium or aluminium-copper alloys.^[44][45]
• Some guitar models sport aluminium diamond plates on the surface of the instruments, usually either chrome or black. Kramer Guitars and Travis Bean are both known for having produced guitars with necks made of aluminium, which gives the instrument a very distinct sound.

Aluminium is usually alloyed – it is used as pure metal only when corrosion resistance and/or workability is more important than strength or hardness. A thin layer of aluminium can be deposited onto a flat surface by physical vapour deposition or (very infrequently) chemical vapour deposition or other chemical means to form optical coatings and mirrors.

Aluminium alloys in structural applications

Main article: Aluminium alloy

Aluminium foam

Aluminium alloys with a wide range of properties are used in engineering structures. Alloy systems are classified by a number system (ANSI) or by names indicating their main alloying constituents (DIN and ISO).

The strength and durability of aluminium alloys vary widely, not only as a result of the components of the specific alloy, but also as a result of heat treatments and manufacturing processes. A lack of knowledge of these aspects has from time to time led to improperly designed structures and gained aluminium a bad reputation.

One important structural limitation of aluminium alloys is their fatigue strength. Unlike steels, aluminium alloys have no well-defined fatigue limit, meaning that fatigue failure eventually occurs, under even very small cyclic loadings. This implies that engineers must assess these loads and design for a fixed life rather than an infinite life.

Another important property of aluminium alloys is their sensitivity to heat. Workshop procedures involving heating are complicated by the fact that aluminium, unlike steel, melts without first glowing red. Forming operations where a blow torch is used therefore require some expertise, since no visual signs reveal how close the material is to melting. Aluminium alloys, like all structural alloys, also are subject to internal stresses following heating operations such as welding and casting. The problem with aluminium alloys in this regard is their low melting point, which make them more susceptible to distortions from thermally induced stress relief. Controlled stress relief can be done during manufacturing by heat-treating the parts in an oven, followed by gradual cooling—in effect annealing the stresses.

The low melting point of aluminium alloys has not precluded their use in rocketry; even for use in constructing combustion chambers where gases can reach 3500 K. The Agena upper stage engine used a regeneratively cooled aluminium design for some parts of the nozzle, including the thermally critical throat region.

Another alloy of some value is aluminium bronze (Cu-Al alloy).

 AYORINDE AYODEJI.