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76-449: Developed independently in 1984 by General Motors and Sumitomo Special Metals , neodymium magnets are the strongest type of permanent magnet available commercially. They have replaced other types of magnets in many applications in modern products that require strong permanent magnets, such as electric motors in cordless tools, hard disk drives and magnetic fasteners. NdFeB magnets can be classified as sintered or bonded, depending on

152-529: A 15% stake in AeroVironment . In 1989, GM acquired half of Saab Automobile 's car operations for $ 600 million. In August 1990, Robert Stempel became CEO of the company, succeeding Roger Smith . GM cut output significantly and suffered losses that year due to the early 1990s recession . In 1990, GM debuted the General Motors EV1 (Impact) concept, a battery electric vehicle , at

228-530: A British producer of high-performance sports cars . In 1987, in conjunction with AeroVironment , GM built the Sunraycer , which won the inaugural World Solar Challenge and was a showcase of advanced technology. Much of the technology from Sunraycer found its way into the Impact prototype electric vehicle (also built by Aerovironment) and was the predecessor to the General Motors EV1 . In 1988, GM acquired

304-664: A DC current through a separate winding to control an inductor's impedance . Varying the current in the control winding moves the operating point up and down on the saturation curve, controlling the alternating current through the inductor. These are used in variable fluorescent light ballasts , and power control systems. Saturation is also exploited in fluxgate magnetometers and fluxgate compasses . In some audio applications, saturable transformers or inductors are deliberately used to introduce distortion into an audio signal. Magnetic saturation generates odd-order harmonics, typically introducing third and fifth harmonic distortion to

380-510: A breakthrough in heat treating still in use today as ASTM A255. GM established Detroit Diesel the next year. In 1939, the company founded Motors Insurance Corporation and entered the vehicle insurance market. The same year, GM introduced the Hydramatic , the first affordable and successful automatic transmission , for the 1940 Oldsmobile. During World War II , GM produced vast quantities of armaments, vehicles, and aircraft for

456-482: A continuation of its diversification plans, GMAC formed GMAC Mortgage and acquired Colonial Mortgage as well as the servicing arm of Norwest Mortgage in 1985. This acquisition included an $ 11 billion mortgage portfolio. The same year, GM acquired the Hughes Aircraft Company for $ 5 billion in cash and stock and merged it into Delco Electronics . The following year, GM acquired 59.7% of Lotus Cars ,

532-957: A controlling interest in North American Aviation and merged it with the General Aviation Manufacturing Corporation . The GM labor force participated in the formation of the United Auto Workers labor union in 1935, and in 1936 the UAW organized the Flint Sit-Down Strike , which initially idled two key plants in Flint, Michigan, and later spread to 6 other plants including those in Janesville, Wisconsin and Fort Wayne, Indiana . In Flint, police attempted to enter

608-717: A dominant force in neodymium magnet production, based on their control of much of the world's rare-earth mines. The United States Department of Energy has identified a need to find substitutes for rare-earth metals in permanent magnet technology and has funded such research. The Advanced Research Projects Agency-Energy has sponsored a Rare Earth Alternatives in Critical Technologies (REACT) program, to develop alternative materials. In 2011, ARPA-E awarded 31.6 million dollars to fund Rare-Earth Substitute projects. Because of its role in permanent magnets used for wind turbines , it has been argued that neodymium will be one of

684-470: A few cubic centimeters are strong enough to cause injuries to body parts pinched between two magnets, or a magnet and a ferrous metal surface, even causing broken bones. Magnets that get too near each other can strike each other with enough force to chip and shatter the brittle magnets, and the flying chips can cause various injuries, especially eye injuries . There have even been cases where young children who have swallowed several magnets have had sections of

760-485: A greater distance than other types of magnet. In some cases, chipped magnets can act as a fire hazard as they come together, sending sparks flying as if they were a lighter flint , because some neodymium magnets contain ferrocerium . General Motors General Motors Company ( GM ) is an American multinational automotive manufacturing company headquartered in Detroit , Michigan, United States. The company

836-504: A high saturation alloy such as Permendur is often used. In electronic circuits , transformers and inductors with ferromagnetic cores operate nonlinearly when the current through them is large enough to drive their core materials into saturation. This means that their inductance and other properties vary with changes in drive current. In linear circuits this is usually considered an unwanted departure from ideal behavior. When AC signals are applied, this nonlinearity can cause

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912-401: A large magnetic field B which extends out from the material. This is called magnetization . The stronger the external magnetic field H , the more the domains align, yielding a higher magnetic flux density B . Eventually, at a certain external magnetic field, the domain walls have moved as far as they can, and the domains are as aligned as the crystal structure allows them to be, so there

988-405: A limit on the minimum size of their cores. This is one reason why high power motors, generators, and utility transformers are physically large; to conduct the large amounts of magnetic flux necessary for high power production, they must have large magnetic cores. In applications in which the weight of magnetic cores must be kept to a minimum, such as transformers and electric motors in aircraft,

1064-591: A magnet it is the unpaired electrons, aligned so that their spin is in the same direction, which generate the magnetic field. This gives the Nd 2 Fe 14 B compound a high saturation magnetization ( J s ≈ 1.6   T or 16   kG ) and a remanent magnetization of typically 1.3 teslas. Therefore, as the maximum energy density is proportional to J s , this magnetic phase has the potential for storing large amounts of magnetic energy ( BH max  ≈ 512   kJ/m or 64   MG·Oe ). This magnetic energy value

1140-524: A namesake defense vehicles division which produces military vehicles for the United States government and military, the vehicle safety, security, and information services provider OnStar , the auto parts company ACDelco , a namesake financial lending service , and majority ownership in the self-driving cars enterprise Cruise LLC . The company originated as a holding company for Buick established on September 16, 1908, by William C. Durant ,

1216-453: A negative coefficient, meaning the coercivity along with the magnetic energy density ( BH max ) decreases as temperature increases. Neodymium-iron-boron magnets have high coercivity at room temperature, but as the temperature rises above 100 °C (212 °F), the coercivity decreases drastically until the Curie temperature (around 320 °C or 608 °F). This fall in coercivity limits

1292-874: A neodymium-boron compound. The diamagnetic boron atoms do not contribute directly to the magnetism but improve cohesion by strong covalent bonding. The relatively low rare earth content (12% by volume, 26.7% by mass) and the relative abundance of neodymium and iron compared with samarium and cobalt makes neodymium magnets lower in price than the other major rare-earth magnet family, samarium–cobalt magnets . Although they have higher remanence and much higher coercivity and energy product, neodymium magnets have lower Curie temperature than many other types of magnets. Special neodymium magnet alloys that include terbium and dysprosium have been developed that have higher Curie temperature, allowing them to tolerate higher temperatures. Sintered Nd 2 Fe 14 B tends to be vulnerable to corrosion , especially along grain boundaries of

1368-542: A program to develop a lightweight two-stroke diesel engine for possible usage in automobiles. Soon after, GM acquired Electro-Motive Company and the Winton Engine Co. , and in 1941, it expanded EMC's realm to locomotive engine manufacturing. In 1932, GM acquired Packard Electric (not to be confused with the Packard car company, which merged with Studebaker years later). The following year, GM acquired

1444-501: A sintered magnet. This type of corrosion can cause serious deterioration, including crumbling of a magnet into a powder of small magnetic particles, or spalling of a surface layer. This vulnerability is addressed in many commercial products by adding a protective coating to prevent exposure to the atmosphere. Nickel, nickel-copper-nickel and zinc platings are the standard methods, although plating with other metals, or polymer and lacquer protective coatings, are also in use. Neodymium has

1520-422: A strategy by CEO Roger Smith to derive at least 10% of its annual worldwide revenue from non-automotive sources. GM also intended to have EDS handle its bookkeeping, help computerize factories, and integrate GM's computer systems. The transaction made Ross Perot the largest shareholder of GM; however, disagreements with Roger Smith led the company to buy all shares held by Ross Perot for $ 750 million in 1986. In

1596-644: Is a widely recognized international classification. Their values range from N28 up to N55 with a theoretical maximum at N64. The first letter N before the values is short for neodymium, meaning sintered NdFeB magnets. Letters following the values indicate intrinsic coercivity and maximum operating temperatures (positively correlated with the Curie temperature ), which range from default (up to 80 °C or 176 °F) to TH (230 °C or 446 °F). Grades of sintered NdFeB magnets: There are two principal neodymium magnet manufacturing methods: Bonded neo Nd-Fe-B powder

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1672-551: Is about 18 times greater than "ordinary" ferrite magnets by volume and 12 times by mass. This magnetic energy property is higher in NdFeB alloys than in samarium cobalt (SmCo) magnets , which were the first type of rare-earth magnet to be commercialized. In practice, the magnetic properties of neodymium magnets depend on the alloy composition, microstructure, and manufacturing technique employed. The Nd 2 Fe 14 B crystal structure can be described as alternating layers of iron atoms and

1748-414: Is applied during the moulding process, orienting the field of the completed magnet. In 2015, Nitto Denko of Japan announced their development of a new method of sintering neodymium magnet material. The method exploits an "organic/inorganic hybrid technology" to form a clay-like mixture that can be fashioned into various shapes for sintering. It is said to be possible to control a non-uniform orientation of

1824-417: Is applied to the material, the domains' magnetic fields are oriented in random directions, effectively cancelling each other out, so the net external magnetic field is negligibly small. When an external magnetizing field H is applied to the material, it penetrates the material and aligns the domains, causing their tiny magnetic fields to turn and align parallel to the external field, adding together to create

1900-451: Is bound in a matrix of a thermoplastic polymer to form the magnets. The magnetic alloy material is formed by splat quenching onto a water-cooled drum. This metal ribbon is crushed to a powder and then heat-treated to improve its coercivity . The powder is mixed with a polymer to form a mouldable putty, similar to a glass-filled polymer . This is pelletised for storage and can later be shaped by injection moulding . An external magnetic field

1976-569: Is most known for owning and manufacturing four automobile brands: Chevrolet , Buick , GMC , and Cadillac . By total sales, it has continuously been the largest automaker in the United States, and was the largest in the world for 77 years before losing the top spot to Toyota in 2008. General Motors operates manufacturing plants in eight countries. In addition to its four core brands, GM also holds interests in Chinese brands Baojun and Wuling via SAIC-GM-Wuling Automobile . GM further owns

2052-400: Is negligible change in the domain structure on increasing the external magnetic field above this. The magnetization remains nearly constant, and is said to have saturated. The domain structure at saturation depends on the temperature. Saturation puts a practical limit on the maximum magnetic fields achievable in ferromagnetic-core electromagnets and transformers of around 2 T, which puts

2128-744: Is not constant, but depends on H . In saturable materials the relative permeability increases with H to a maximum, then as it approaches saturation inverts and decreases toward one. Different materials have different saturation levels. For example, high permeability iron alloys used in transformers reach magnetic saturation at 1.6–2.2   teslas (T), whereas ferrites saturate at 0.2–0.5   T. Some amorphous alloys saturate at 1.2–1.3   T. Mu-metal saturates at around 0.8   T. Ferromagnetic materials (like iron) are composed of microscopic regions called magnetic domains , that act like tiny permanent magnets that can change their direction of magnetization. Before an external magnetic field

2204-499: Is the result of several factors. The most important is that the tetragonal Nd 2 Fe 14 B crystal structure has exceptionally high uniaxial magnetocrystalline anisotropy ( H A ≈ 7   T – magnetic field strength H in units of A/m versus magnetic moment in A·m). This means a crystal of the material preferentially magnetizes along a specific crystal axis but is very difficult to magnetize in other directions. Like other magnets,

2280-516: Is used as a magnetic crane which is a lifting device that lifts objects by magnetic force . These cranes lift ferrous materials like steel plates, pipes, and scrap metal using the persistent magnetic field of the permanent magnets without requiring a continuous power supply. Magnetic cranes are used in scrap yards, shipyards , warehouses , and manufacturing plants . The greater forces exerted by rare-earth magnets create hazards that may not occur with other types of magnet. Neodymium magnets larger than

2356-625: The Fortune 500 and 50th on the Fortune Global 500 . In 2023, the company was ranked 70th in the Forbes Global 2000 . In 2021, GM announced its intent to end production of vehicles using internal combustion engines by 2035, as part of its plan to achieve carbon neutrality by 2040. By 1900, William C. Durant 's Durant-Dort Carriage Company of Flint, Michigan , had become the largest manufacturer of horse-drawn vehicles in

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2432-517: The 2-mode hybrid system in the Chevrolet Tahoe , GMC Yukon , Cadillac Escalade , and pickup trucks . Magnetic saturation Seen in some magnetic materials, saturation is the state reached when an increase in applied external magnetic field H cannot increase the magnetization of the material further, so the total magnetic flux density B more or less levels off. (Though, magnetization continues to increase very slowly with

2508-848: The Allies of World War II . In 1940, GM's William S. Knudsen served as head of U.S. wartime production for President Franklin Roosevelt , and by 1942, all of GM's production was to support the war. GM's Vauxhall Motors manufactured the Churchill tank series for the Allies, instrumental in the North African campaign . However, its Opel division, based in Germany, supplied the Wehrmacht with vehicles. Politically, Sloan, as head of GM at

2584-461: The CPSC is now 14, and there are now new warning label requirements. The strength and magnetic field homogeneity on neodymium magnets has also opened new applications in the medical field with the introduction of open magnetic resonance imaging (MRI) scanners used to image the body in radiology departments as an alternative to superconducting magnets that use a coil of superconducting wire to produce

2660-522: The Cadillac V8-6-4 variable-cylinder engines. GM sold Frigidaire in 1979. Although Frigidaire had between $ 450 million and $ 500 million in annual revenues, it was losing money. Robert Lee of GM invented the neodymium magnet , which was fabricated by rapid solidification, in 1984. This magnet is commonly used in products like a computer hard disk. The same year, GM acquired Electronic Data Systems for $ 2.5 billion from Ross Perot as part of

2736-520: The General Motors Acceptance Corporation (GMAC), which provides financing to automotive customers, was formed. In 1920, du Pont orchestrated the removal of Durant once again and replaced him with Alfred P. Sloan . At a time when GM was competing heavily with Ford Motor Company , Sloan established annual model changes, making previous years' models "dated" and created a market for used cars . He also implemented

2812-426: The H field increases, the B field approaches a maximum value asymptotically , the saturation level for the substance. Technically, above saturation, the B field continues increasing, but at the paramagnetic rate, which is several orders of magnitude smaller than the ferromagnetic rate seen below saturation. The relation between the magnetizing field H and the magnetic field B can also be expressed as

2888-682: The LA Auto Show . It was the first car with zero emissions marketed in the US in over three decades. The Impact was produced as the EV1 for the 1996 model year and was available only via lease from certain dealers in California and Arizona. In 1999–2002, GM ceased production of the vehicles and started to not renew the leases, disappointing many people, allegedly because the program would not be profitable and would cannibalize its existing business. All of

2964-567: The Rapid Motor Vehicle Company of Pontiac, Michigan , and the Reliance Motor Car Company of Detroit, Michigan (predecessors of GMC ) in 1909. Durant, with the board's approval, also tried acquiring Ford Motor Company , but needed an additional $ 2 million. Durant over- leveraged GM in making acquisitions, and was removed by the board of directors in 1910 at the order of the bankers who backed

3040-765: The Yellow Cab Manufacturing Company the same year, and its president, John D. Hertz , joined the board of directors of GM; it acquired the remainder of the company in 1943. In 1926, the company introduced the Pontiac brand and established the General Motors Group Insurance Program to provide life insurance to its employees. The following year, after the success of the 1927 model of the Cadillac LaSalle designed by Harley Earl , Sloan created

3116-472: The corporate spin-off of Electronic Data Systems . In 1997, GM sold the military businesses of Hughes Aircraft Company to Raytheon Company for $ 9.5 billion in stock and the assumption of debt. In February 2000, Rick Wagoner was named CEO, succeeding Smith. The next month, GM gave 5.1% of its common stock, worth $ 2.4 billion, to acquire a 20% share of Fiat . In December 2000, GM announced that it would begin phasing out Oldsmobile . The brand

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3192-417: The digestive tract pinched between two magnets, causing injury or death. Also this could be a serious health risk if working with machines that have magnets in or attached to them. The stronger magnetic fields can be hazardous to mechanical and electronic devices, as they can erase magnetic media such as floppy disks and credit cards , and magnetize watches and the shadow masks of CRT -type monitors at

3268-537: The "Art and Color Section" of GM and named Earl as its first director. Earl was the first design executive to be appointed to leadership at a major American corporation. Earl created a system of automobile design that is still practiced today. At the age of 24, Bill Mitchell was recruited by Earl to the design team at GM, and he was later appointed as Chief Designer of Cadillac. After Earl retired in December 1958, Mitchell took over automotive design for GM. Also in 1926

3344-588: The EV1s were eventually returned to General Motors, and except for around 40 which were donated to museums with their electric powertrains deactivated, all were destroyed. The documentary film Who Killed the Electric Car? covered the EV1 story. In November 1992, John F. Smith Jr. became CEO of the company. In 1993, GM sold Lotus Cars to Bugatti . In 1996, in a return to its automotive basics, GM completed

3420-684: The United States. Durant was averse to automobiles, but fellow Flint businessman James H. Whiting , owner of Flint Wagon Works , sold him the Buick Motor Company in 1904. Durant formed the General Motors Company in 1908 as a holding company , borrowing a naming convention from General Electric . GM's first acquisition was Buick , which Durant already owned, then Olds Motor Works on November 12, 1908. Under Durant, GM went on to acquire Cadillac , Elmore , Welch , Cartercar , Oakland (the predecessor of Pontiac ),

3496-460: The closing mechanism of modern sport parachute equipment. They are the main metal in the formerly popular desk-toy magnets, "Buckyballs" and "Buckycubes", though some U.S. retailers have chosen not to sell them because of child-safety concerns, and they have been banned in Canada for the same reason. While a similar ban has been lifted in the United States in 2016, the minimum age requirement advised by

3572-452: The company acquired Fisher Body , its supplier of automobile bodies. GM acquired Allison Engine Company and began developing a 1,000 horsepower liquid-cooled aircraft engine in 1929. The same year, GM acquired 80% of Opel , which at that time had a 37.5% market share in Europe, for $ 26 million. It acquired the remaining 20% in 1931. In the late-1920s, Charles Kettering embarked on

3648-480: The company in 1915 after a disagreement with Durant. GM was reincorporated in Detroit in 1916 as General Motors Corporation and became a public company via an initial public offering . By 1917, Chevrolet had become successful enough that Durant, with the backing of Samuel McLaughlin and Pierre S. du Pont , reacquired a controlling interest in GM. The same year, GM acquired Samson Tractor . Chevrolet Motor Company

3724-716: The diesel-hybrid market, the Opel Astra diesel engine hybrid concept vehicle was rolled out in January 2005. Later that year, GM sold its Electro-Motive Diesel locomotive division to private equity firms Berkshire Partners and Greenbriar Equity Group. GM paid $ 2 billion to sever its ties with Fiat in 2005, severing ties with the company due to an increasingly contentious dispute. GM began adding its " Mark of Excellence " emblem on all new vehicles produced and sold in North America in mid-2005. However, after

3800-486: The efficiency of the magnet under high-temperature conditions, such as in wind turbines and hybrid vehicle motors. Dysprosium (Dy) or terbium (Tb) is added to curb the fall in performance from temperature changes. This addition makes the magnets more costly to produce. Neodymium magnets are graded according to their maximum energy product , which relates to the magnetic flux output per unit volume. Higher values indicate stronger magnets. For sintered NdFeB magnets, there

3876-428: The field due to paramagnetism .) Saturation is a characteristic of ferromagnetic and ferrimagnetic materials, such as iron , nickel , cobalt and their alloys. Different ferromagnetic materials have different saturation levels. Saturation is most clearly seen in the magnetization curve (also called BH curve or hysteresis curve) of a substance, as a bending to the right of the curve (see graph at right). As

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3952-482: The first hydrogen fuel cell car ever produced. Though fuel cells have existed since the early 1800s, General Motors was the first to use a fuel cell, supplied by Union Carbide , to power the wheels of a vehicle with a budget of "millions of dollars". In the 1960s, GM was an early proponent of V6 engines , but quickly lost interest as the popularity of muscle cars increased. GM demonstrated gas turbine vehicles powered by kerosene , an area of interest throughout

4028-497: The gasoline was harmful to various biological organisms including humans. Evidence shows that corporate executives understood the health implications of tetraethyllead from the beginning. As an engineer for GM, Midgley also developed chlorofluorocarbons , which have now been banned due to their contribution to climate change . Under the encouragement of GM President Alfred P. Sloan Jr., GM acquired Vauxhall Motors for $ 2.5 million in 1925. The company also acquired an interest in

4104-445: The generation of harmonics and intermodulation distortion. To prevent this, the level of signals applied to iron core inductors must be limited so they don't saturate. To lower its effects, an air gap is created in some kinds of transformer cores. The saturation current , the current through the winding required to saturate the magnetic core, is given by manufacturers in the specifications for many inductors and transformers. On

4180-664: The industry, but abandoned the alternative engine configuration due to the 1973 oil crisis . In partnership with Boeing , GM's Delco Defense Electronics Division designed the Lunar Roving Vehicle , which traversed the surface of the Moon, in 1971. The following year, GM produced the first rear wheel anti-lock braking system for two models: the Toronado and Eldorado. In 1973, the Oldsmobile Toronado

4256-601: The largest seller of horse-drawn vehicles at the time. The first half of the 20th century saw the company grow into an automotive behemoth through acquisitions; going into the second half, the company pursued innovation and new offerings to consumers as well as collaborations with NASA to develop the earliest electric vehicles . The current entity was established in 2009 after the General Motors Chapter 11 reorganization . As of 2024 , General Motors ranks 25th by total revenue out of all American companies on

4332-637: The loans to keep GM in business. The action of the bankers was partially influenced by the Panic of 1910–1911 that followed the earlier enforcement of the Sherman Antitrust Act of 1890 . In 1911, Charles F. Kettering of Dayton Engineering Laboratories Company (DELCO) and Henry M. Leland invented and patented the first electric starter in America. In November 1911, Durant co-founded Chevrolet with race car driver Louis Chevrolet , who left

4408-441: The magnetic permeability : μ = B / H {\displaystyle \mu =B/H} or the relative permeability μ r = μ / μ 0 {\displaystyle \mu _{r}=\mu /\mu _{0}} , where μ 0 {\displaystyle \mu _{0}} is the vacuum permeability . The permeability of ferromagnetic materials

4484-476: The magnetic field in the sintered material to locally concentrate the field, for instance to improve the performance of electric motors. Mass production is planned for 2017. As of 2012, 50,000   tons of neodymium magnets are produced officially each year in China, and 80,000   tons in a "company-by-company" build-up done in 2013. China produces more than 95% of rare earth elements and produces about 76% of

4560-439: The magnetic field. Neodymium magnets are used as a surgically placed anti-reflux system which is a band of magnets surgically implanted around the lower esophageal sphincter to treat gastroesophageal reflux disease (GERD). They have also been implanted in the fingertips in order to provide sensory perception of magnetic fields, though this is an experimental procedure only popular among biohackers and grinders . Neodymium

4636-689: The main objects of geopolitical competition in a world running on renewable energy . This perspective has been criticized for failing to recognize that most wind turbines do not use permanent magnets and for underestimating the power of economic incentives for expanded production. In its pure form, neodymium has magnetic properties—specifically, it is antiferromagnetic , but only at low temperatures, below 19 K (−254.2 °C; −425.5 °F). However, some compounds of neodymium with transition metals such as iron are ferromagnetic , with Curie temperatures well above room temperature. These are used to make neodymium magnets. The strength of neodymium magnets

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4712-564: The manufacturing process used. General Motors (GM) and Sumitomo Special Metals independently discovered the Nd 2 Fe 14 B compound almost simultaneously in 1984. The research was initially driven by the high raw materials cost of samarium-cobalt permanent magnets (SmCo), which had been developed earlier. GM focused on the development of melt-spun nanocrystalline Nd 2 Fe 14 B magnets, while Sumitomo developed full-density sintered Nd 2 Fe 14 B magnets. GM commercialized its inventions of isotropic Neo powder, bonded neo magnets, and

4788-519: The neodymium magnet alloy is composed of microcrystalline grains which are aligned in a powerful magnetic field during manufacture so their magnetic axes all point in the same direction. The resistance of the crystal lattice to turning its direction of magnetization gives the compound a very high coercivity , or resistance to being demagnetized. The neodymium atom can have a large magnetic dipole moment because it has 4 unpaired electrons in its electron structure as opposed to (on average) 3 in iron. In

4864-475: The other hand, saturation is exploited in some electronic devices. Saturation is employed to limit current in saturable-core transformers , used in arc welding , and ferroresonant transformers which serve as voltage regulators . When the primary current exceeds a certain value, the core is pushed into its saturation region, limiting further increases in secondary current. In a more sophisticated application, saturable core inductors and magnetic amplifiers use

4940-486: The plant to arrest strikers, leading to violence; in other cities, the plants were shuttered peacefully. The strike was resolved on February 11, 1937, when GM recognized the UAW as the exclusive bargaining representative for its workers and gave workers a 5% raise and permission to speak in the lunchroom. Walter E. Jominy and A.L. Boegehold of GM invented the Jominy end-quench test for hardenability of carbon steel in 1937,

5016-528: The pricing strategy used by car companies today. The pricing strategy had Chevrolet , Pontiac , Oldsmobile , Buick , and Cadillac priced from least expensive to most, respectively. In 1921, Thomas Midgley Jr. , an engineer for GM, discovered tetraethyllead (leaded gasoline) as an antiknock agent, and GM patented the compound because ethanol could not be patented. This led to the development of higher compression engines resulting in more power and efficiency. The public later realized that lead contained in

5092-512: The related production processes by founding Magnequench in 1986 (Magnequench has since become part of Neo Materials Technology, Inc., which later merged into Molycorp ). The company supplied melt-spun Nd 2 Fe 14 B powder to bonded magnet manufacturers. The Sumitomo facility became part of Hitachi , and has manufactured but also licensed other companies to produce sintered Nd 2 Fe 14 B magnets. Hitachi has held more than 600 patents covering neodymium magnets. Chinese manufacturers have become

5168-487: The reorganization in 2009, the company no longer added the logo, saying that emphasis on its four core divisions would downplay the GM logo. In 2005, Edward T. Welburn was promoted to the newly created position of vice president, GM Global Design, making him the first African American to lead a global automotive design organization and the highest-ranking African American in the US motor industry at that time. On July 1, 2016, he retired from General Motors after 44 years. He

5244-504: The time, was an ardent opponent of the New Deal , which bolstered labor unions and public transport . Sloan admired and supported Adolf Hitler . Nazi armaments chief Albert Speer allegedly said in 1977 that Hitler "would never have considered invading Poland" without synthetic fuel technology provided by General Motors. GM was compensated $ 32 million by the U.S. government because its German factories were bombed by U.S. forces during

5320-518: The war. Effective January 28, 1953, Charles Erwin Wilson , then GM president, was named by Dwight D. Eisenhower as United States Secretary of Defense . In December 1953, GM acquired Euclid Trucks , a manufacturer of heavy equipment for earthmoving , including dump trucks , loaders and wheel tractor-scrapers , which later spawned the Terex brand. Alfred P. Sloan retired as chairman and

5396-626: The world's total rare-earth magnets, as well as most of the world's neodymium. Neodymium magnets have replaced alnico and ferrite magnets in many of the myriad applications in modern technology where strong permanent magnets are required, because their greater strength allows the use of smaller, lighter magnets for a given application. Some examples are: The greater strength of neodymium magnets has inspired new applications in areas where magnets were not used before, such as magnetic jewelry clasps, keeping up foil insulation, children's magnetic building sets (and other neodymium magnet toys ) and as part of

5472-490: Was consolidated into GM on May 2, 1918, and the same year GM acquired United Motors , a parts supplier founded by Durant and headed by Alfred P. Sloan for $ 45 million, and the McLaughlin Motor Car Company , founded by R. S. McLaughlin , became General Motors of Canada Limited. In 1919, GM acquired Guardian Frigerator Company , part-owned by Durant, which was renamed Frigidaire . Also in 1919,

5548-560: Was eventually discontinued in 2004, seven years after it had become the first American car brand to turn 100. In May 2004, GM delivered the first full-sized pickup truck hybrid vehicles , the 1/2-ton Chevrolet Silverado / GMC Sierra trucks. These mild hybrids did not use electrical energy for propulsion, like GM's later designs. Later, the company debuted another hybrid technology, co-developed with DaimlerChrysler and BMW , in diesel-electric hybrid powertrain manufactured by Allison Transmission for transit buses. Continuing to target

5624-566: Was replaced by Michael Simcoe . In 2006, GM introduced a bright yellow fuel cap on its vehicles to remind drivers that cars can operate using E85 ethanol fuel . They also introduced another hybrid vehicle that year, the Saturn Vue Green Line . In 2008, General Motors committed to engineering half of its manufacturing plants to be landfill-free by recycling or reusing waste in the manufacturing process. Continuing their environmental-conscious development, GM started to offer

5700-608: Was succeeded by Albert Bradley in April 1956. In 1962, GM introduced the first ever turbocharged production car in the world in the Oldsmobile Cutlass Turbo-Jetfire. Two years later, the company introduced its " Mark of Excellence " logo and trademark at the 1964 New York World's Fair . The company used the mark as their main corporate identifier until 2021. GM released the Electrovan in 1966,

5776-558: Was the first retail car sold with a passenger airbag . Thomas Murphy became CEO of the company, succeeding Richard C. Gerstenberg in November 1974. GM installed its first catalytic converters in its 1975 models. From 1978 to 1985, GM pushed the benefits of diesel engines and cylinder deactivation technologies. However, it had disastrous results due to poor durability in the Oldsmobile diesels and drivability issues in

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