Metal Types Objectives l Know the types of
Metal Types
Objectives l Know the types of metals and examples of them
Steel. l l is an alloy of iron and carbon and usually other metals There are four major steel making processes: l l the Bessemer furnace the open hearth furnace electric furnace the oxygen furnace
There are two general types of steel: carbon and alloy. l Approximately 80 to 90 percent of steel produced is carbon steel. l Carbon steels contain 0. 05 to 1 percent carbon and less than 1. 5 percent of the other elements.
There are two general types of steel l The strength of steel increases as the carbon content increases, but increase hardness, brittleness, and difficulty of fabrication
Additive Effects l l Tungsten l produce tool steels that will maintain a cutting edge at high heat. Aluminum l provide a hardened surface. Molybdenum l increase the hardness and the endurance Chromium l increases the wear and corrosion resistance l More than 4 percent chromium are stainless. l l Sulfur: l aid in machinability Silicon l improve electrical, mechanical, and thermal characteristics. Nickel l increase the toughness and strength. Vanadium l increase the strength.
How is metal classified? l These metals can be broken down into four groups l l Ferrous Metals Non-ferrous metals Ferrous Alloys Non-ferrous Alloys
Ferrous metals l l Main ingredient is iron. Pig iron, cast iron, wrought iron, and steel/
l Pig iron or cured iron l l iron ore changed to pig iron by a blast furnace. Steel l iron characterized chiefly by its carbon content.
Cast iron l l A product of pig iron Contains large amounts of carbon It is brittle and granular in structure. Gray cast l l White cast iron l l sprockets, stoves, and manifolds. agitators in grain drills Malleable cast iron l conventional mower guards.
B. Non-ferrous metals l l Have no iron and are made up of a single element. Ex: l aluminum, copper, lead, magnesium, nickel, tin, tungsten, zinc, silver, and gold.
Aluminum l is a silver-white, malleable, ductile metal. l It is known for it’s electrical conductivity, heat conductivity, rust resistance, and light weight.
Copper l l l reddish-brown in color is used for tubes, wire, sheets, and plates. It has excellent workability, either hot or cold, and the highest electrical and heat conductivity of all commercial metals.
Lead l l l has a bluish-white color and a bright luster. It is soft, highly malleable, and ductile; has slight tenacity; and is a poor conductor of electricity. It is used for making pipe and containers for corrosive liquids.
Magnesium l l is a very lightweight, silver-white metal, which is malleable and ductile and burns in air. It is usually found in the alloy known as dowmetal. l It is useful for airplane bodies, truck and auto wheels, ladders, lawn mower frames, and any place where weight reduction is important.
Nickel l Is a hard, malleable, ductile, tenacious white metal that is somewhat magnetic. l It is valuable for the alloys it forms with other metals.
Tin l does not corrode in humid conditions, adheres tenaciously to iron, has a low melting point l used extensively in solder, brass, bronze, and pewter.
Tungsten l l l one of the heaviest metals used for making filaments for incandescent lamps. Tungsten carbide is almost as hard as diamond and is used extensively for cutting tools.
Zinc l l l bluish-white metal at ordinary temperatures is brittle but malleable at high temperatures used as a galvanizing metal coating to prevent corrosion.
Silver l l l shiny, white metal used mostly for ornamental work, jewelry, and table-ware. Silver is the best conductor of electricity. Gold is most often used for ornamental jewelry.
C. Ferrous alloys l Metals made up largely of ferrous materials but having other elements in sufficient quantities to change the ferrous characteristics.
Manganese steel l can stand strain, hammering, shock, and hard wear. l It is used for the jaws of ore crushers, power shovels, chains, gears, and safes.
Chromium steel l resists rust, shock, scratches, and stains. l It is used for bearings, safes, ore crushers, and is the basis for high-quality stainless steel.
Nickel steel l is strong, hard, elastic, tough, and durable. l It does not rust easily l used for springs, cables, axles, shafts, and armor plate.
Stainless steel l seldom rusts l used for cutlery, precision measuring instruments, dentistry supplies, auto parts, and engine valves.
Tungsten steel l l adds hardness to steel and allows it to withstand heat. Tungsten carbide is the hardest metal known and is used for various cutting surfaces.
Molybdenum steels l l known for their strength and hardness used for hacksaw blades, high-grade machinery parts, bearings, and auto parts.
Vanadium steel l l is tough and can withstand great shocks as well as resist corrosion. used for springs, gears, and vibrating parts of machinery.
High-speed steel l contains one or more alloying elements
D. Non-ferrous alloys l Made up of two or more nonferrous elements.
Brass l l l an alloy of copper and zinc. It is ductile, malleable, and acid resistant. Bronze l l an alloy of copper and tin behaves very much like brass when welded.
Solder types l l lead and tin solder copper and zinc alloy solder silver and copper alloy solder. Pewter l an alloy of 92 percent tin, 5 percent antimony and 3 percent copper.
Monel l is an alloy of 60 percent nickel and 40 percent copper.
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