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Aerospace Materials
Aerospace materials are materials, frequently metal alloys, that have either been developed for, or have come to prominence through their use for aerospace purposes. These uses often require exceptional performance, strength or heat resistance, even at the cost of considerable expense in their production or machining. Others are chosen for their long-term reliability in this safety-conscious field, particularly for their resistance to fatigue. The field of materials engineering is an important one within aerospace engineering. Its practice is defined by the international standards bodies who maintain standards for the materials and processes involved. Engineers in this field may often have studied for degrees or post-graduate qualifications in it as a speciality. History Edwardian period The first aerospace materials were those long-established and often naturally occurring materials used to construct the first aircraft. These included such mundane materials as timber for w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rolls Royce RB
Roll or Rolls may refer to: Movement about the longitudinal axis * Roll angle (or roll rotation), one of the 3 angular degrees of freedom of any stiff body (for example a vehicle), describing motion about the longitudinal axis ** Roll (aviation), one of the aircraft principal axes of rotation of an aircraft (angle of tilt to the left or right measured from the longitudinal axis) ** Roll (ship motion), one of the ship motions' principal axes of rotation of a ship (angle of tilt to the port or starboard measured from the longitudinal axis) * Rolling ''manoeuvre'', a manoeuvre of any stiff body (for example a vehicle) around its roll axis: ** Roll, an aerobatic maneuver with an airplane, usually referring to an aileron roll, but sometimes instead a barrel roll, rudder roll or slow roll ** Kayak roll, a maneuver used to right a capsized kayak ** Roll program, an aerodynamic maneuver performed in a rocket launch * Roll rate (or roll velocity), the angular speed at which an aircraft ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Irish Linen
Irish linen ( ga, Línéadach Éireannach) is the name given to linen produced in Ireland (including both the Republic of Ireland and Northern Ireland). Linen is cloth woven from, or yarn spun from, flax fibre, which was grown in Ireland for many years before advanced agricultural methods and more suitable climate led to the concentration of quality flax cultivation in northern Europe. Most of the world crop of quality flax is now grown in northern France, Belgium and the Netherlands. Since about the 1950s to 1960s, the flax fibre for Irish linen yarn has been imported almost exclusively from France, Belgium, and the Netherlands. It is bought by spinners who produce yarn, which is then sold to weavers (or knitters) who produce fabric. Irish linen spinning has now virtually ceased, yarns being imported from places such as the eastern part of the European Union and China. Weaving today consists mainly of plain linens for niche, top-of-the-range, apparel uses. Linen damask weaving ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piston
A piston is a component of reciprocating engines, reciprocating pumps, gas compressors, hydraulic cylinders and pneumatic cylinders, among other similar mechanisms. It is the moving component that is contained by a cylinder and is made gas-tight by piston rings. In an engine, its purpose is to transfer force from expanding gas in the cylinder to the crankshaft via a piston rod and/or connecting rod. In a pump, the function is reversed and force is transferred from the crankshaft to the piston for the purpose of compressing or ejecting the fluid in the cylinder. In some engines, the piston also acts as a valve by covering and uncovering ports in the cylinder. __TOC__ Piston engines Internal combustion engines An internal combustion engine is acted upon by the pressure of the expanding combustion gases in the combustion chamber space at the top of the cylinder. This force then acts downwards through the connecting rod and onto the crankshaft. The connecting rod is att ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fighting occurring throughout Europe, the Middle East, Africa, the Pacific, and parts of Asia. An estimated 9 million soldiers were killed in combat, plus another 23 million wounded, while 5 million civilians died as a result of military action, hunger, and disease. Millions more died in genocides within the Ottoman Empire and in the 1918 influenza pandemic, which was exacerbated by the movement of combatants during the war. Prior to 1914, the European great powers were divided between the Triple Entente (comprising France, Russia, and Britain) and the Triple Alliance (containing Germany, Austria-Hungary, and Italy). Tensions in the Balkans came to a head on 28 June 1914, following the assassination of Archduke Franz Ferdin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hodder & Stoughton
Hodder & Stoughton is a British publishing house, now an imprint (trade name), imprint of Hachette (publisher), Hachette. History Early history The firm has its origins in the 1840s, with Matthew Hodder's employment, aged 14, with Messrs Jackson and Walford, the official publisher for the Congregational church, Congregational Union. In 1861 the firm became Jackson, Walford and Hodder; but in 1868 Jackson and Walford retired, and Thomas Wilberforce Stoughton joined the firm, creating Hodder & Stoughton. Hodder & Stoughton published both religious and secular works, and its religious list contained some progressive titles. These included George Adam Smith, George Adam Smith's ''Isaiah'' for its ''Expositor’s Bible'' series, which was one of the earliest texts to identify multiple authorship in the Book of Isaiah. There was also a sympathetic ''Life of Francis of Assisi, St Francis'' by Paul Sabatier (theologian), Paul Sabatier, a French Protestant pastor. Matthew Hodder ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Y Alloy
Y alloy is a nickel-containing aluminium alloy. It was developed by the British National Physical Laboratory during World War I, in an attempt to find an aluminium alloy that would retain its strength at high temperatures. Duralumin, an aluminium alloy containing 4% copper was already known at this time. Its strength, and its previously unknown age hardening behaviour had made it a popular choice for zeppelins. Aircraft of the period were largely constructed of wood, but there was a need for an aluminium alloy suitable for making engines, particularly pistons, that would have the strength of duralumin but could retain this when in service at high temperatures for long periods. The National Physical Laboratory began a series of experiments to study new aluminium alloys. Experimental series "Y" was successful, and gave its name to the new alloy. Like duralumin, this was a 4% copper alloy, but with the addition of 2% nickel and 1.5% magnesium. This addition of nickel was an innovation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Physical Laboratory (United Kingdom)
The National Physical Laboratory (NPL) is the national measurement standards laboratory of the United Kingdom. It is one of the most extensive government laboratories in the UK and has a prestigious reputation for its role in setting and maintaining physical standards for British industry. Founded in 1900, it is one of the oldest metrology institutes in the world. Research and development work at NPL has contributed to the advancement of many disciplines of science, including the development early computers in the late 1940s and 1950s, construction of the first accurate atomic clock in 1955, and the invention and pioneering implementation of packet switching in the 1960s, which is today one of the fundamental technologies of the Internet. The former heads of NPL include many individuals who were pillars of the British scientific establishment. NPL is based at Bushy Park in Teddington, west London. It is under the management of the Department for Business, Energy and Industrial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HMSO
The Office of Public Sector Information (OPSI) is the body responsible for the operation of His Majesty's Stationery Office (HMSO) and of other public information services of the United Kingdom. The OPSI is part of the National Archives of the United Kingdom and is responsible for Crown copyright. The OPSI announced on 21 June 2006 that it was merging with the National Archives. The merger took place in October 2006. The OPSI continues to discharge its roles and responsibilities from within the structure of the National Archives. Controller of HMSO and Director of OPSI The Controller of HMSO is also the Director of OPSI. HMSO continues to operate from within the expanded remit of OPSI. The Controller of HMSO also holds the offices of Kings's Printer of Acts of Parliament, King's Printer for Scotland and Government Printer for Northern Ireland. By virtue of holding these offices OPSI publishes, through HMSO, the '' London Gazette'', ''Edinburgh Gazette'', ''Belfast Gazette'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminum Alloy
An aluminium alloy (or aluminum alloy; see spelling differences) is an alloy in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon, tin, nickel and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories heat-treatable and non-heat-treatable. About 85% of aluminium is used for wrought products, for example rolled plate, foils and extrusions. Cast aluminium alloys yield cost-effective products due to the low melting point, although they generally have lower tensile strengths than wrought alloys. The most important cast aluminium alloy system is Al–Si, where the high levels of silicon (4–13%) contribute to give good casting characteristics. Aluminium alloys are widely used in engineering structures and components where light weight or corrosion resistance is required.I. J. Polmear, ''Light Alloys'', Arnold, 1995 Alloys c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Age Hardening
Precipitation hardening, also called age hardening or particle hardening, is a heat treatment technique used to increase the yield strength of malleable materials, including most structural alloys of aluminium, magnesium, nickel, titanium, and some steels and stainless steels. In superalloys, it is known to cause yield strength anomaly providing excellent high-temperature strength. Precipitation hardening relies on changes in solid solubility with temperature to produce fine particles of an impurity phase, which impede the movement of dislocations, or defects in a crystal's lattice. Since dislocations are often the dominant carriers of plasticity, this serves to harden the material. The impurities play the same role as the particle substances in particle-reinforced composite materials. Just as the formation of ice in air can produce clouds, snow, or hail, depending upon the thermal history of a given portion of the atmosphere, precipitation in solids can produce many different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
