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molybdenum, 1.75 to 2.5 columbium plus tantalum, 1.5 to 2.5 copper, and as much as 2.5 cobalt; Hastelloy S, 14.5 to 17 chromium, 14 to 16.5 molybdenum, and as much as 3 iron and 2 cobalt; Hastelloy C-276, 15 to 17 molybdenum, 14.5 to 16.5 chromium, 4 to 7 iron, 3 to 4.5 tung- sten, and as much as 2.5 cobalt. Hastelloy B-3 excels in resistance to hydrochloric and sulfuric acids. Hastelloy G provides greater high-temperature strength than Hastelloy C but is not as corrosion-resistant. Hastelloy C-276 is widely used in incinerator scrubbing systems used to dispose of chemical wastes, which, after combustion, form corrosive acidic wastestreams when absorbed in water. Other incinerator applica- tions include mesh-type mist eliminators and draft-inducing fan wheels. Hastelloy C-22 contains 20 to 22.5% chromium, 12.5 to 14.5 molybdenum, 2 to 6 iron, 2.5 to 3.5 tungsten, 2.5 maximum cobalt, and small amounts of other elements, including 0.15 maximum car- bon. It is used for the quench body and variable venturi of incinera- tor systems. The alloy is brittle after welding, however, so welded components should be free from vibrations. Hastelloy C-2000, with 23 chromium, 16 molybdenum, 1.6 copper, 0.08 maximum silicon, and 0.01 maximum carbon, combines excellent resistance to reducing environments with excellent resistance to oxidizing environments. Room-temperature tensile yield strength ranges from 52,000 to 57,000 lb/in 2 (359 to 393 MPa) and elongation from 62 to 68% depend- ing on thickness. MAT 21, of Mitsubishi Materials of Japan, has 19 molybdenum and 1.8 titanium. It features one-tenth to one-third less corrosion weight loss than Hastelloy C-276 in nitric, hydrofluoric, phosphoric, and sulfuric acids and is almost as strong. Incoloy 800, though iron-base, is often grouped with these alloys. It contains 46% iron, 32.5 nickel, and 21 chromium. Nickel-base (42%) Incoloy 825 contains 30% iron, 21.5 chromium, 3 molybde- num, and 2.3 copper. Hastelloy X, which provides substantial strength and oxidation resistance at temperatures to about 2200°F (1204°C), contains 20 to 23% chromium, 17 to 20 iron, 8 to 10 molybdenum, 0.5 to 2.5 cobalt, and 0.2 to 1 tungsten. Solution-treated rapidly cooled sheet has room- temperature tensile properties of 114,000 lb/in 2 (786 MPa) ultimate strength, 52,000 lb/in 2 (359 MPa) yield strength, 43% elongation, and 28.5 ϫ 10 6 lb/in 2 (197,000 MPa) modulus. At 1800°F (982°C), these properties are 22,500 lb/in 2 (155 MPa), 16,000 lb/in 2 (110 MPa), 45%, and 18.3 ϫ 10 6 lb/in 2 (126,000 MPa), respectively. The alloy has a den- sity of 0.297 lb/in 3 (8,221 kg/m 3 ), a coefficient of thermal expansion at 70 to 1600°F (21 to 871°C) of 9.1 ϫ 10 Ϫ6 /°F (16.3 ϫ 10 Ϫ6 /K), and a melting range of 2300 to 2470°F (1260 to 1354°C). The alloy is widely used for gas-turbine parts and other applications requiring heat and 630 NICKEL ALLOYS Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Materials, Their Properties and Uses oxidation resistance. Though mainly a wrought alloy, it also can be investment cast. There are a great variety of high-temperature, high-strength nickel alloys, called superalloys because of their outstanding strength, creep resistance, stress-rupture strength, and oxidation resis- tance at high temperatures. They are widely used for gas turbines, especially aircraft engines. Most of these alloys contain substantial chromium for oxidation resistance; refractory metals for solid-solution strengthening; small amounts of grain-boundary-strengthening ele- ments, such as carbon, boron, hafnium, and/or zirconium; and alu- minum and titanium for strengthening by precipitation of an Ni(Al,Ti) compound known as gamma prime during age-hardening. Among the well-known wrought alloys are D-979; GMR-235-D; IN 102; Inconel 625, 700, 706, 718, 722, X750, and 751; MAR-M 200 and 412; Rene 41, 95, and 100; Udimet 500 and 700; and Waspaloy. Inconel 718SPF is tailored for superplastic forming, as the letters in the alloy designation imply. Having an ultrafine grain size, ASTM 10 or less, it can be superplastically formed at a temperature of about 1740°F (950°C) at low strain rates. At these conditions, very little pressure, such as 300 lb/in 2 (2.1 MPa), is needed to achieve large deformation. Cast alloys include B-1900; GMR-235-D; IN 100, 162, 738, and 792; M252; MAR-M 200, 246, and 421; Nicrotung; Rene 41, 77, 80, and 100; and Udimet 500 and 700. Some wrought alloys are also suitable for casting, primarily investment casting. Controlled-expansion nickel superalloys have a nickel-iron-cobalt austenitic matrix optimized for minimal thermal expansion and are strengthened by gamma precipitation promoted by aluminum, columbium, and titanium additions. Specific alloys, of Inco Alloys International and Carpenter Technologies, respectively, include Incoloy 903 and Pyromet CTX-1, Incoloy 907 and Pyromet CTX-3, and Incoloy 909 and Pyromet CTX-909. These alloys are used mainly in aircraft gas-turbine engines to maintain tight clearances between rotating and stationary components over a wide temperature range. Being chromium-free and, thus, lacking oxidation resistance in air, they must have coatings applied for service temperatures above 1000°F (538°C). Carpenter Technologies’ Thermo-Span alloy contains 5.5% chromium, increasing oxidation resistance to 1300°F (704°C). The alloy matches the thermal expansivity of Pyromet CTX-909 at 200°F (95°C)—4.5 ϫ 10 Ϫ6 /°F (8.1 ϫ 10 Ϫ6 /K)—and at 400°F (205°C)—4.3 ϫ 10 Ϫ6 /°F (7.7 ϫ 10 Ϫ6 /K). At higher temperatures, how- ever, its expansivity is greater, 18% greater at 1000°F. Incoloy 908, containing 49% nickel, 41.5 iron, 4 chromium, 3 columbium, 1.5 tita- nium, and 1 aluminum, is a sheathing material for superconducting magnets in fusion reactors. At the superconducting temperature of NICKEL ALLOYS 631 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Materials, Their Properties and Uses Ϫ452°F (Ϫ269°C), the alloy’s tensile yield strength is 180,000 lb/in 2 (1240 MPa) and its toughness is greater than that of 9%-nickel steel. Nicrofer 45, or Alloy 45, and Nicrofer 6025 HT, or Alloy 602 CA, are nickel-chromium-iron alloys from VDM Technologies. Alloy 45 contains at least 45% nickel, 26 chromium, 21 iron, 2.5 sili- con, 0.05 carbon, and 0.05 cerium. Formation of a protective chromium oxide layer with a subjacent silicon-oxide layer gives the alloy excellent resistance to oxidizing, reducing, nitriding, and sulfur media even under alternating conditions, and waste-incineration environments at temperatures up to 1560°F (850°C). Also, the alloy is approved for pressure vessels operating at temperatures from Ϫ320 to 1020°F (Ϫ196 to 550°C). Physical properties include a density of 0.289 lb/in 3 (8000 kg/m 3 ), a specific heat of 0.12 Btu/lb . °F (500 J/kg . K), a thermal conductivity of 90 Btu . in/ft 2 . h . °F (13 W/m · k), an electrical resistivity of 710 Ω circ mil/ft (118 ␮Ω·cm), and a modulus of elasticity of 28,000,000 lb/in 2 (193,000 MPa). Tensile properties are 90,000 lb/in 2 (621 MPa) ultimate strength, 35,000 (241 MPa) yield strength, and 35% elongation. Creep-rupture strength for 10,000 h at 1000°F (538°C) is 17,800 lb/in 2 (123 MPa). Alloy 602 CA has at least 24 chromium, 8 iron, 1.8 aluminum, 0.15 carbon, 0.1 titanium, 0.05 yttrium, 0.01 zirconium, and maximum amounts of 0.5 silicon, 0.1 manganese, and 0.1 copper. It also features excellent oxidation resis- tance, even under cyclic conditions, plus corrosion resistance in car- burizing environments and high-temperature creep resistance. It has a density of 0.285 lb/in 3 (7889 kg/m 3 ), 31,200,000 lb/in 2 (215,100 MPa) modulus, 94,300 lb/in (650 MPa) minimum ultimate tensile strength, 43,500 lb/in 2 (300 MPa) minimum yield strength, 30% minimum elon- gation, and a creep-rupture strength of 6100 lb/in 2 (42 MPa) for 10,000 h at 1200°F (649°C). Typical uses include oxygen preheaters, radiant heater tubes, furnace parts, and exhaust gas systems. In addition to the above families, there are specialty nickel alloys for glass sealing and other applications. Paramagnetic alloys called Nitinol, developed by the Naval Ordnance Laboratory, are intermetallic compounds of nickel and titanium rather than nickel-titanium alloys. The compound TiNi contains theoretically 54.5% nickel, but the alloys may contain Ti 2 Ni and TiNi 3 with about 50 to 60% nickel. The TiNi and nickel-rich alloys are paramagnetic, with a permeability value of 1.002, compared with the unity value of a vacuum. A 54.5% nickel alloy has a tensile strength of 110,000 lb/in 2 (758 MPa) with elongation of about 15%, and Rockwell C hardness of 35. The alloys close to the TiNi compo- sition are ductile and can be cold-rolled. The nickel-rich alloys are hot-rolled. They can be hardened by heat treatment to give Rockwell C hardnesses to 68 and tensile strengths to 140,000 lb/in 2 632 NICKEL ALLOYS Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Materials, Their Properties and Uses (965 MPa). This class of alloy can also be modified with small amounts of silicon or aluminum, forming complex intermetallic compounds that can be solution-treated. The Nitinols, with nickel content ranging from 53 to 57%, are known as memory alloys, or shape-memory alloys, because of their ability to be deformed and then return to their original shape when heated to their transformation temperature. For example, a straight piece of Nitinol wire can be bent in multiple places and then straightened by simply applying heat to the bent regions. The alloys are ductile and have excellent fatigue resistance and damping capac- ity. Applications include fire-sprinkler actuators, tap water antiscald- ing devices, greenhouse window hinges, flow regulators, spacecraft solar-panel releases, various toys and novelties, and underwire brassieres (that return to shape at room temperature after warm machine washings). Nickel alloy powders are used for flame-sprayed coatings for hard surfacing and corrosion resistance. Metco 14E, of Metco, Inc., is an alloy powder containing 14% chromium, 3.5 silicon, 2.75 boron, 4 iron, 0.60 carbon, with the balance nickel. The alloy is self- fluxing and gives an extremely hard coating. Colmonoy 72, of Wall Colmonoy Corp., is a similar alloy powder but with 13% tungsten. Coatings have a melting point of 1950°F (1066°C) and retain hard- ness and wear resistance at high temperatures. Colmonoy 88, with 17.3% tungsten, 15 chromium, and roughly similar iron, sili- con, boron, and carbon contents, provides a Rockwell C hardness of 59 to 64 and somewhat greater abrasion resistance. NICKEL BRONZE. A name given to bronzes containing nickel, which usually replaces part of the tin, producing a tough, fine-grained, and corrosion-resistant metal. A common nickel bronze containing 88% copper, 5 tin, 5 nickel, and 2 zinc has a tensile strength of 48,000 lb/in 2 (330 MPa), elongation 42%, and Brinell hardness 86 as cast. When it is heat-treated or age-hardened, the tensile strength is 87,000 lb/in 2 (599 MPa), elongation 10%, and Brinell hardness 196. Small amounts of lead take away the age-hardening quality of the alloy and lower the ductility. But small amounts of nickel added to bearing bronzes increase the resistance to compression and shock without impairing the plasticity. A bearing bronze of this nature contains 73 to 80% copper, 15 to 20 lead, 5 to 10 tin, and 1 nickel. In the leaded nickel-copper, which contains 1% nickel, 1 lead, 0.2 phosphorus, and the balance copper, a nickel phosphide is dispersed in the alloy by heat treatment, giving a machinability of 80% that of a free-cutting brass. The tensile strength is 85,000 lb/in 2 (586 MPa), elongation 5%, and electric conductivity 55% that of copper. NICKEL BRONZE 633 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Materials, Their Properties and Uses For decorative bronze parts, nickel is used to give a white color. In the hardware industry, the old name Chinese bronze was used for these white alloys. At least 10% nickel is needed to give a white color. This amount also gives corrosion resistance to the alloy. When more than 15% nickel is used, the bronzes are difficult to machine unless some lead is added. Hardware and plumbing fixtures of these alloys do not require plating. NICKEL-CHROMIUM STEEL. Steel containing both nickel and chromium, usually in a ratio of 2 to 3 parts nickel to 1 chromium. The 2:1 ratio gives great toughness, and the nickel and chromium are intended to balance each other in physical effects. The steels are especially suited for large sections which require heat treat- ment because of their deep and uniform hardening. Hardness and toughness are the characteristic properties of these steels. Nickel-chromium steel containing 1 to 1.5% nickel, 0.45 to 0.75 chromium, and 0.38 to 0.80 manganese is used throughout the car- bon ranges for case-hardened parts and for forgings where high tensile strength and great hardness are required. Low nickel-chromium steels, having more carbon, 0.60 to 0.80%, are used for drop-forging dies and other tools. Nickel-chromium steels may have temper brittleness, or low impact resistance, when improperly cooled after heat treatment. A small amount of molybdenum is sometimes added to prevent this brittle- ness. A nickel-chromium coin steel used by the Italian government for coins, was a stainless-steel type cotaining 22% chromium, 12 nickel, and some molybdenum. Low-carbon nickel-chromium steels are water-hardening, but those with appreciable amounts of alloying elements require oil quenching. Air-hardening steels contain up to 4.5% nickel and 1.6 chromium, but are brittle unless tempered in oil to strengths below 200,000 lb/in 2 (1,379 MPa). The alloy known as Krupp analysis steel contains 4% nickel and 1.5 chromium. NICKEL-MOLYBDENUM STEEL. Alloy steels used mostly in composi- tions of 1.5% nickel and 0.15 to 0.25 molybdenum, with varying per- centages of carbon up to 0.50%. These steels are characterized by uniform properties and are readily forged and heat-treated. Molybdenum toughens the steels, and in the case-hardening steels gives a tough core. Roller bearings are made of this class of steel. Superalloy steel is 3160 steel. A 5%-nickel steel with 0.30% carbon and 0.60 molybdenum has a tensile strength of 175,000 to 230,000 lb/in 2 (1,207 to 1,586 MPa) with elongation 12 to 22%, depending on heat treatment. Molybdenum is more frequently added to the steels 634 NICKEL-CHROMIUM STEEL Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Materials, Their Properties and Uses containing also chromium, the molybdenum giving air-hardening properties, reducing distortion, and making the steels more resistant to oxidation. NICKEL ORES. Nickel occurs in minerals as sulfides, silicates, and arsenides, the most common being pyrrhotite, or magnetic pyrites, a sulfide of iron of formula Fe 1Ϫx S, where x is between 0 and 0.2. When x is zero, the mineral is called troilite. Pyrrhotite has nickel associated with the iron sulfide. The ore of Copper Cliff, Ontario, is calcined to remove the sulfur, and the nickel is removed, leaving a fine magnetite which is pelletized and fired to give an iron concentrate of 68% iron. The chief sulfide ore deposit at Sudbury, Ontario, contains sulfides of iron, nickel, and copper, and small amounts of other elements; and some of the matte after removal of the iron and sulfur is used as Monel metal without separating the natural alloy. The extensive ore deposits at Lynn Lake, Manitoba, yield an ore averaging 1.74% nickel and 0.75 copper. The garnierite, or noumeite, of New Caledonia is a nickel silicate containing also iron and magnesium. It is amorphous and earthy, an apple-green color, with a specific gravity of 2.2 to 2.8, and Mohs hardness of 3 to 4. The ore contains about 5% nickel and is smelted with gypsum to a matte of sulfides of nickel and iron, the sulfur coming from the gyp- sum. This is then bessemerized, and the matte crushed, roasted to oxide, and reduced to nickel. The material exported from New Caledonia under the name of fonte is a directly smelted cast iron containing about 30% nickel. A minor ore of nickel called millerite, occurring in Europe and in Wisconsin, is a nickel sulfide, NiS, containing theoretically 64.7% nickel. It is found usually in radiating groups of slender crystals with a specific gravity of 5.6, Mohs hardness 3.5, and of a pale-yellow color and metallic luster. Nicolite, NiAs, is a minor ore containing theoretically 43.9% nickel, usually with iron, cobalt, and sulfur. It is found in Canada, Germany, and Sweden. The mineral occurs mas- sive, with a specific gravity of 7.5, Mohs hardness 5 to 5.5, and a pale-copper color. Nickel is also produced as a by-product from copper ores. NICKEL SILVER. A name applied to an alloy of copper, nickel, and zinc, which is practically identical with alloys known in the silver- ware trade as German silver. Packfong, meaning white copper, is an old name for these alloys. The very early nickel silvers contained some silver and were used for silverware. Wessell’s silver contained about 2%, and Ruolz silver about 20. Baudoin alloy, a French metal, contained 72% copper, 16 nickel, 1.8 cobalt, 2.5 silver, and the NICKEL SILVER 635 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Materials, Their Properties and Uses balance zinc, but the white jewelry alloys called Paris metal and Lutecine contained about 2% tin instead of silver. The English silver known as Alpaca, used as a base metal for silver-plated tableware, had about 65% copper, 20 zinc, 13 nickel, and 2 silver. Such an alloy takes a fine polish, has a silvery-white color, and is resistant to corro- sion. Lake copper, sometimes classified as a nickel silver, is a silver- bearing copper with varying amounts of silver up to about 30 oz/ton (0.91 metric ton). Nickel whitens brass and makes it harder and more resistant to corrosion, but the alloys are more difficult to cast because of shrink- age and absorption of gases. They are also subject to fire cracking and are more difficult to roll and draw than brass. Some three dozen standard wrought alloys (C73150 to C79900) and four standard cast alloys (C97300 to C97800) are designated nickel silvers. Depending on the alloy, copper content of wrought alloys ranges from 48 to 80% and nickel content from about 7 to 25, with zinc the balance except for smaller quantities of other elements, mainly manganese, iron, and lead. The cast alloys range from about 55 to 65% copper, 12 to 25 nickel, 2.5 to 21 zinc, 2 to 10 lead, with lesser amounts of other elements. The most common alloy, nickel silver C75200, nominally con- tains 65% copper and 18 nickel and, thus, is often referred to as nickel silver 65–18. The alloy’s electrical conductivity is about 6% that of copper, and its thermal conductivity is 19 Btu/(ft и h и °F) [33 W/(m и K)]. Tensile properties for thin, flat products in the annealed condition are about 60,000 lb/in 2 (414 MPa) ultimate strength, 30,000 lb/in 2 (207 MPa) yield strength, and 30% elongation. Cold-working to the hard temper triples yield strength and markedly reduces ductility. Wire, which has similar tensile prop- erties annealed, can be cold-worked to still greater tensile strength. Modulus of elasticity in tension is 18 ϫ 10 6 lb/in 2 (124,000 MPa). All of the cast alloys are suitable for sand and investment casting and some also for centrifugal and permanent- mold casting. The strongest of these alloys, nickel silver C97800, has typical tensile properties of 55,000 lb/in 2 (379 MPa) ultimate strength, 30,000 lb/in 2 (207 MPa) yield strength, 15% elongation, and 19 ϫ 10 6 lb/in 2 (131,000 MPa) modulus. Applications for wrought alloys include hollowware and tableware, watch and camera parts, hardware, dairy equipment, costume jewelry, nameplates, keys, fasteners, and springs. The cast alloys are used for fittings, valves, ornaments, pump parts, and marine equipment. Over the years, nickel silvers have been known by a variety of names. Benedict metal originally had 12.5% nickel, with 2 parts copper to 1 zinc, but the alloy used for hardware and plumbing fixtures 636 NICKEL SILVER Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Materials, Their Properties and Uses contains about 57% copper, 2 tin, 9 lead, 20 zinc, and 12 nickel. The cast metal has a strength of 35,000 lb/in 2 (241 MPa) with elongation of 15%. The white alloy known as dairy bronze, used for casting dairy equipment and soda-fountain parts, has 63% copper, 4 tin, 5 lead, 8 zinc, and 20 nickel. The higher-nickel alloys have a more per- manent white finish for parts subject to corrosion. Ambrac 854 is a wrought metal with 65% copper, 30 nickel, and 5 zinc. Pope’s Island white metal, used for jewelry, has 67% copper, 19.75 nickel, and 13.25 zinc. Victor metal, an alloy of 50% copper, 35 zinc, and 15 nickel, is used for cast fittings. It is a white metal with a yellow shade. It casts easily and machines well. For threaded parts and for casting metals, the nickel silvers usually contain some lead for easier machining. White nickel brass, for cast parts for trim, is a standard 18% nickel alloy with or without lead. Silveroid, an English alloy for this use, is a copper-nickel alloy with- out zinc. An English alloy for tableware, under the name of Newloy, contains 35% nickel, 64 copper, and 1 tin. The stainless nickel used for silverware by Viners, Ltd., has 30% nickel, 60 copper, and 10 zinc and is deoxidized with manganese copper, using borax as a top flux. A number of other alloys of copper, nickel, and zinc are termed nickel brass. A Cu-20Zn-5Ni nickel brass is used for parts of euro bimetal coins. Nickel-silicon brass contains a very small percent- age of silicon, usually about 0.60%, which forms a nickel silicide, Ni 2 Si, increasing the strength and giving heat-treating properties. Rolled nickel-silicon brass, containing 30% zinc, 2.5 nickel, and 0.65 silicon, has a tensile strength of 114,000 lb/in 2 (786 MPa). Imitation silver, for hardware and fittings, is actually a nickel brass containing 57% copper, 25 zinc, 15 nickel, and 3 cobalt. The bluish color of the cobalt neutralizes the yellow cast of the nickel and produces a silver-white alloy. Silvel is another nickel brass, containing 67.5% copper, 26 zinc, and 6.5 nickel, with sometimes a little cobalt. Nickel brass is an alloy used where white color and corrosion resistance are desired. Seymourite, an alloy of 64% copper, 18 nickel, and 18 zinc pro- duced by Seymour Mfg. Co., has a white color and corrosion resis- tance. Nickeline, used for hardware, is 58 to 60% copper, 16.5 nickel, 2 tin, and the remainder zinc. It has high strength, a white color, and casts well. Nickelene is an old name applied to nickel brass of various compositions, but an alloy patented in 1912 under this name had 55% copper, 12.5 nickel, 20.5 zinc, 10 lead, and 2 tin. Most of these alloys have good casting qualities, but do not machine easily unless containing some lead. Up to 2% lead does not affect the color or decrease strength greatly. NICKEL SILVER 637 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Materials, Their Properties and Uses NICKEL STEEL. Steel containing nickel as the predominant alloying element. The first nickel steel produced in the United States was made in 1890 by adding 3% nickel in a Bessemer converter. The first nickel-steel armor plate, with 3.5% nickel, was known as Harveyized steel. Small amounts of nickel steel, however, had been used since ancient times, coming from meteoric iron. The nickel iron of meteorites, known in mineralogy as taenite, contains about 26% nickel. Nickel added to carbon steel increases the strength, elastic limit, hardness, and toughness. It narrows the hardening range but lowers the critical range of steel, reducing danger of warpage and cracking, and balances the intensive deep-hardening effect of chromium. The nickel steels are also of finer structure than ordinary steels, and the nickel retards grain growth. When the percentage of nickel is high, the steel is very resistant to corrosion. At high nickel contents, the metals are referred to as iron-nickel alloys or nickel-iron alloys. The steel is nonmagnetic above 29% nickel, and the maximum perme- ability is at about 78% nickel. The lowest thermal expansion is at 36% nickel. The percentage of nickel in nickel steels usually varies from 1.5 to 5%, with up to 0.80 manganese. The bulk of nickel steels contain 2 and 3.5% nickel. They are used for armor plate, structural shapes, rails, heavy-duty machine parts, gears, automobile parts, and ordnance. The standard ASTM structural nickel steel used for building construction contains 3.25% nickel, 0.45 carbon, and 0.70 man- ganese. This steel has tensile strength from 85,000 to 100,000 lb/in 2 (586 to 690 MPa) and a minimum elongation of 18%. An automobile steel contains 0.10 to 0.20% carbon, 3.25 to 3.75 nickel, 0.30 to 0.60 manganese, and 0.15 to 0.30 silicon. When heat-treated, it has a tensile strength up to 80,000 lb/in 2 (552 MPa) and an elongation 25 to 35%. Forgings for locomotive crankpins, containing 2.5% nickel, 0.27 carbon, and 0.88 man- ganese, have a tensile strength of 83,000 lb/in 2 (572 MPa), elonga- tion 30%, and reduction of area 62%. A nickel-vanadium steel, used for high-strength cast parts, contains 1.5% nickel, 1 man- ganese, 0.28 carbon, and 0.10 vanadium. The tensile strength is 90,000 lb/in 2 (621 MPa) and elongation 25%. Univan steel for high-strength locomotive castings is a nickel-vanadium steel of this type. Unionaloy steel is an abrasion-resistant steel. The federal specifications for 3.5% nickel carbon steel call for 3.25 to 3.75% nickel and 0.25 to 0.30 carbon. This steel has a tensile strength of 85,000 lb/in 2 (586 MPa) and elongation 18%. When oil-quenched, a hot-rolled, 3.5% nickel, medium-carbon steel, Steel 2330, develops a tensile strength up to 220,000 lb/in 2 (1,516 MPa) 638 NICKEL STEEL Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Materials, Their Properties and Uses and Brinell hardness of 223 to 424, depending upon the drawing temperature. Standard 3.5 and 5% nickel steels are regular products of the steel mills, though they are often sold under trade names. Steels with more than 3.5% nickel are too expensive for ordinary structural use. Steels with more than 5% nickel are difficult to forge, but the very high-nickel steels are used when corrosion-resistant properties are required. Nicloy, used in fork tubing to resist the cor- rosive action of paper-mill liquors and oil-well brines, contains 9% nickel, 0.10 chromium, 0.05 molybdenum, 0.35 copper, 0.45 man- ganese, 0.20 silicon, and 0.09 maximum carbon. The heat-treated steel has a tensile strength of 110,000 lb/in 2 (758 MPa), with elonga- tion 35%. The cryogenic steels, or low-temperature steels, for such uses as liquid-oxygen vessels, are usually high-nickel steels. ASTM steel A-353, for liquid-oxygen tanks at temperatures to Ϫ320°F (Ϫ196°C), contains 9% nickel, 0.85 manganese, 0.25 silicon, and 0.13 carbon. It has a tensile strength of 95,000 lb/in 2 (655 MPa) with elongation of 20%. A 9% nickel steel, for temperatures down to Ϫ320°F, contains 9% nickel, 0.80 manganese, 0.30 silicon, and not over 0.13 carbon. It has a minimum tensile strength of 90,000 lb/in 2 (621 MPa) and elongation of 22%. NICKEL SULFATE. The most widely used salt for nickel-plating baths, and known in the plating industry as single nickel salt. It is easily produced by the reaction of sulfuric acid on nickel, and comes in pea- green, water-soluble crystalline pellets of composition NiSO 4 и 7H 2 O, of specific gravity 1.98, melting at about 212°F (100°C). Double nickel salt is nickel ammonium sulfate, NiSO 4 и (NH 4 ) 2 и SO 4 и 6H 2 O, used specifically for plating on zinc. To produce a harder and whiter finish in nickel plating, cobaltous sulfamate, a water-soluble powder of composition Co(NH 2 SO 3 ) 2 и 3H 2 O, is used with nickel sul- fate. Nickel plate has a normal Brinell hardness of 90 to 140, but by controlled processes file-hard plates can be obtained from sulfate baths. Micrograin nickel, with a grain diameter of 0.00002 in (0.00005 cm), is such a hard plate. In electroless plating, nickel sul- fate, a reducing agent, a pH adjuster, and complexing and stabilizing agents are combined to deposit metallic nickel on an immersed object. General American Transportation Co. employs a hypophosphite reductant. The electroless nickel coating is comparable to electrolytic chrome. Other nickel salts are also used for nickel plating. Nickel chlo- ride, NiCl 2 и 6H 2 O, is a green crystalline salt which, when used with boric acid, gives a fine-grained, smooth, hard, strong plate. It requires less power, and the bath is easy to control. Nickel carbonate, 2NiCO 3 и 3Ni(OH) 2 и 4H 2 O, comes in green crystals not soluble in NICKEL SULFATE 639 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Materials, Their Properties and Uses [...]... provide about 40% more parts per given resin quantity Affinity SM 1250 is intended to replace PVC and EVA in appliances, toys, and siding Engage EG 8100 is a general-purpose grade, which with 24% octene comonomer, has a Mooney viscosity of 23, a melt index of 0.013 lb/h (0.006 kg/h), a tensile modulus of 350,000 lb/in 2 (2,413 MPa), an ultimate tensile strength of 1,500 lb/in2 (10 MPa), 800% ultimate... less costly and far tougher than the original Zeonex and is intended for uses where the key properties of Zeonex are not as critical Two grades, Zeonor 102 0 and 1600, have glass-transition temperatures of 212°F (100 °C) and 329°F (165°C), respectively The 102 0 has an impact strength of 0.86 ft lb/in (46 J/m) or about double that of Zeonex 480 Also called red oil, elaine oil, octadecenoic acid, and rapic... oxide or other materials to give particular characteristics Opax is a zirconium oxide with small percentages of silica, sodium oxide, and alumina It is used for hard-glaze dinnerware and wall-tile glaze Zircopax is zirconium silicate, ZrSiO4, with 33.5% silica in the molecule It gives color stability and craze resistance Superpax is a finely milled zirconium silicate powder with an average particle size... zirconium silicates Ultrox 100 0W, for maximum opacity and OPACIFIERS Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies All rights reserved Any use is subject to the Terms of Use as given at the website Materials, Their Properties and Uses 662 OPEN-HEARTH STEEL whiteness, has 65% ZrO2 and 35 SiO2 with particle size of 20... with three atoms of oxygen, O3 It is formed in the air by lightning, or during the evaporation of water, particularly of spray in the sea In minute quantities in the air it is an exhilarant, but pure ozone is an intense poison It has a peculiar odor, which can be detected with 1 part in 20 million parts of air Ozone is a powerful oxidizer, capable of breaking down most organic compounds and bleaching... attracted by a magnet, although liquid oxygen is attracted Ozone absorbs ultraviolet rays, and a normal blanket in the upper ozonosphere at heights of 60,000 to 140,000 ft (18,288 to 42,672 m), with 1 part per 100 ,000 parts of air, shields the earth from excess shortwave radiation from the sun The destruction of the stratospheric ozone layer is resulting in the cutting back in usage of chlorofluorocarbons and... subject to the Terms of Use as given at the website Materials, Their Properties and Uses 658 OLEIC ACID Dow Plastics’ Affinity polyolefin plastomers, Engage polyolefin elastomers, and Index ethylene-styrene copolymers, or interpolymers, are based on the company’s “single-site” Insite metallocene catalysis, introduced in the early 1990s, which imparts very narrow molecular weight distribution and highly... sulfuric acid, but other grades are also used Low- and medium-carbon steels with combinations of chromium and aluminum or nickel, chromium, and aluminum Nitriding consists of exposing steel parts to gaseous ammonia at about 100 0°F (538°C) to form metallic nitrides at the surface The hardest coatings are obtained with aluminum-bearing steels Nitriding of stainless steel is known as Malcomizing After nitriding,... McGraw-Hill Companies All rights reserved Any use is subject to the Terms of Use as given at the website Materials, Their Properties and Uses NITROCELLULOSE 641 tance to corrosion from alkalies, the atmosphere, crude oil, natural gas, combustion products, tap water, and still saltwater Nitrided parts usually grow about 0.001 to 0.002 in (0.003 to 0.005 cm) during nitriding The growth can be removed... of a paste made of finely ground, partly dehydrated ripe olives ground with a small amount of corn oil The olive-infused oil has the flavor of olive Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies All rights reserved Any use is subject to the Terms of Use as given at the website Materials, Their Properties and Uses . 200°F (95°C)—4.5 ϫ 10 Ϫ6 /°F (8.1 ϫ 10 Ϫ6 /K)—and at 400°F (205°C)—4.3 ϫ 10 Ϫ6 /°F (7.7 ϫ 10 Ϫ6 /K). At higher temperatures, how- ever, its expansivity is greater, 18% greater at 100 0°F. Incoloy. to 1600°F (21 to 871°C) of 9.1 ϫ 10 Ϫ6 /°F (16.3 ϫ 10 Ϫ6 /K), and a melting range of 2300 to 2470°F (1260 to 1354°C). The alloy is widely used for gas-turbine parts and other applications requiring. elongation, and 28.5 ϫ 10 6 lb/in 2 (197,000 MPa) modulus. At 1800°F (982°C), these properties are 22,500 lb/in 2 (155 MPa), 16,000 lb/in 2 ( 110 MPa), 45%, and 18.3 ϫ 10 6 lb/in 2 (126,000 MPa),

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