MetalsMajor TopicsMajor Topics con’tHistory of MetalClassification of MetalsAlloysIronMaterials Used to Make IronTypes of IronSteelMill OutputStandard Mill ProductsDesignations of Rolled Steel ShapesExample of DesignationSamples of Steel ShapesSteel WireClassification of SteelStainless SteelStructural SteelSteel ConstructionSteel FastenersWeldingSteel Floor and Roof FramingOpen Web Steel JoistsAluminumLeadZincCopperBronzeBrassNickel, Chromium, and Monel6 Methods of Coating Metal w/ Another MetalClad MetalsGalvanic ActionReferences1MetalsMajor TopicsHistoryClassification of MetalsIronSteelSteel pipe, Tubing, and WireSteel FastenersRivetsStructural BoltsWeldingSteel Floor & Roof FramingMajor Topics con’tAluminumLeadZincCopper and AlloysNickel, Chromium, Cadmium & TitaniumClad MetalsHistory of MetalUsed as early as 8000 B.C.Early civilizations mainly used metal for weapons, tools, and body armor Metal has been used for construction material ranging from simple fasteners to main structural membersClassification of Metals2 main classificationsFerrous- metals containing a large percentage of iron (Fe)Cast ironWrought ironSteelNon-Ferrous- metals which do NOT contain ironAluminumLeadCopperBrassBronzeAlloysAlloy – a substance composed of two or more metalsBlanking- in sheet metalwork, the cutting out of a piece of metal (using a press)Braking - a mechanical bending operation usually performed on sheets and platesCasting - an article formed by solidification of molten metal in a moldCold drawing - drawing metal through a die without the application of heatCold-rolled - metal rolled at room temperature, below the softening point, usually harder, smoother, and more accurately dimensioned that hot-rolled material.Drawing - forcing metal to flow into a desired shape without melting by pulling it through diesEmbossing - creating a raised surface (design) on metal by die pressure or by stamping or hammering on the reverse surfaceExtrusion – forcing a molten metal through a die by pressureForging - heating and hammering or pressing metal into a desired shapeRelated TermsIronOne of the most abundant metals on earthCommercial iron is composed of carbon, manganese, silicon, phosphorus, and sulfurMaterials Used to Make IronIron oreCoke- fuel used to melt iron; derived from coalLimestone- used as a fluxFlux – a material added to react chemically with impurities and remove them from molten metalPig Iron- initial molded product from a blast-furnace; weak & brittle, but very hardTypes of IronCast iron (and gray cast iron)- brittle metals with high compressive strength and capacity to absorb vibration. Lack ductility and therefore should not be hammered or beaten. Relatively corrosion resistant. Contains 2-4 % carbonUsed for gratings, stair components, manhole covers, some pipingWrought iron- soft, corrosion and fatigue resistant, and easily machined. Contains < 1 % carbonUsed for railings, grilles, fences, screens, and various ornamental workSteelA malleable alloy of iron and carbon with substantial quantities of manganese3 main methods for making steelOpen-Hearth processPneumatic (Oxygen) processElectric Furnace processMill OutputIngot- molded square or rectangular blocks of cast metalIngots are further squeezed between rollers to produce:Bloom- a rectangular solid of steel formed from an ingot as an intermediate step in creating rolled steel structural shapes (over 36” square)Billet- a large cylinder or rectangular solid of metal (smaller then 36” square)Slab – if the width is 2x the thickness or moreStandard Mill ProductsAngle- a section of metal rolled, drawn, or extruded through L- Shaped rolls or diesBar- round, square, rectangular, hexagonal, or solid stock of drawn, rolled, or extruded metal. A rod.Channel – a rolled, drawn, or extruded metal section having a U shape.Flat- a rectangular bar whose width is greater than its thicknessPipe, round- a hollow, round section of metal, the size of which is determined by the nominal inside diameter in inchesPipe, square- a hollow, square section of metal, the size is determined by the nominal outside diameter in inchesPlate- a flat piece of metal; various metals are defined as plate by the following thickness criteria: Aluminum==1/4” or more; Copper==.188” or more; Steel (including stainless)== 3/16” or moreDesignations of Rolled Steel ShapesW – wide flange S -- beamsC –channelsL – angles (may be equal or unequal legs)WT or MT – structural teesExample of DesignationW 36 x 300W === a wide flange beam36 === indicates a beam 36” deep300 === weight in lbs/ linear feetSamples of Steel ShapesChannelSquare & Rectangular TubingAngleTeeS-BeamWide FlangeSteel Wire6 million tons of wire produced in the U.S. annuallyShapes are not only round, but may also include: square, rectangular, and polygonalWire is used as the starting material to form nails, bolts, screws, rivets, and welding electrodesTemper- wires hardness, stiffness, and strength is affected by the amount of carbon and alloying agents, number of passes through dies, and the final heat treatmentWire may be produced with different finishes and coated, painted, or plated depending on its intended useClassification of SteelFour main specificationsMethod of manufactureHeat treatmentChemical compositionReference to a recognized standardStainless SteelTo be considered stainless a steel must contain 11.5 % chromiumThere are basic series of stainless steel: 200, 300, 400, & 500 seriesAvailable in many finishes ranging from matte to highly reflective (mirror)Structural SteelConsists of hot-rolled steel section, shapes, and plates not less than 1/8” thickThe most commonly used strength grade is 36,000 psi yield strength (ASTM 36)For heavily loaded members such as columns, girders, or trusses, a high strength, low alloy steel with a yield strength of 50,000 psiSteel Construction3 basic types:Wall bearingSkeleton framingLong-spanLarge industrial buildings, auditoriums, sports arenasOften use steel trusses, steel arches, or rigid bents in this type of constructionSteel Fasteners3 main types of fasteners:RivetsBoltsUnfinished (common, machine)High-strength structural bolts-
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