Metals ppt

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Guided By : Prof Arvind Merchant Prof Suryanarayan Rao

Presented By: Bansari Borda Retail and Exhibition Design Sem 3




A metal is a chemical element that is a good conductor of both electricity and heat and forms cations and ionic bonds with non-metals.  Solid at room temperature, except mercury, which is liquid.  very high melting point.

 shiny when they cut.  good conductors of heat and electricity.  usually strong & malleable so they can be hammered into shape.  metals have higher densities than the majority of nonmetals.




The term 'ferrous' comes from a Latin word ferrum, meaning 'containing iron'. Hence, ferrous metals are all those metals that contain iron.

Ferrous metals may contain small amounts of other elements such as carbon or nickel, in a specific proportion, that are added to achieve the desired properties. All the ferrous metals are generally magnetic and have high tensile strength. Now that you know what ferrous metals are, let us have a look at a ferrous metals list.


1. Iron 2. Cast Iron 3. Wrought Iron 4. Galvanized Iron

1. 2. 3. 4. 5. 6.

Steel Mild Steel Carbon Steel Stainless Steel HSLA Steel (high-strength low-alloy Weathering Steel


Iron is a metal extracted mainly from the iron ore hematite. It oxidizes readily in air and water to form Fe2O3 and is rarely found as a free element.

Iron is believed to be the sixth most abundant element in the universe


Ingot iron is a commercially pure iron (99.85% iron) that is easil y formed and possesses good ductility and corrosion resistance. The chemical analysis and properties of this iron and the lowest carbon steel are practically the same. The lowest carbon steel, known as dead-soft, has about 0.06% more carbon than ingot iron. In iron the carbon content is considered an impurity and in steel it is considered an alloying element. The primary use for ingot iron is for galvanized and enameled sheet.


1. Pig iron is the intermediate product of smelting iron ore with coke and resin. 2. Cast into pigs in preparation for conversion into cast iron, wrought iron or steel. 3. Pig iron has a very high carbon content, typically 3.5 - 4.5%, which makes it very brittle and not useful directly as a material except for limited applications.


Cast iron is another commonly used ferrous metal. It is made up of 2 to 6% of carbon and 94 to 98% of iron. It is hard and strong but quite brittle. Cast iron has a high compressive strength and is resistant to oxidation. It can be classified into different varieties like gray cast iron, malleable cast iron and white cast iron. Cast iron is normally used in the manufacture of heavy crushing machinery, machine tool parts, brake drums, car cylinder blocks, machine handles and gear wheels, plumbing material, etc.


1. 2. 3. 4. 5. 6.

7. 8. 9.

Piping & Fittings Ornamental Ironwork Hardware Base Metal for Porcelain Enamelled Plumbing Fixtures Floor & Wall Brackets for Railings Circular Stairs Manhole Cover Gratings

Methods Of Identification

Appearance: Grey with a granular surface Dropping: gives out a dull note

Grinding: Gives off a few dull sparks Effect of Heating: No change


Wrought iron contains less than 0.008% carbon. As it is almost 100% pure iron, it is highly resistant to corrosion and oxidation. It is strong and tough, yet, fibrous and ductile. Wrought iron can be welded, machined and plated easily. It is used to make ornamental gates and railings. APPLICATION: 1.

Piping & Fittings for Plumbing

2.

Heating & Air-conditioning

3.

Ornamental Ironwork.


Iron coated with zinc to prevent rust. The process is achieved thru hot-dip galvanizing. APPLICATION: - Metal Decking - Roofing & Accessories - Ceiling Framing - Wall Framing - Piping


1. Alloys of iron and carbon

2. Carbon content is no more than 2% 3. Alloy elements is composed of phosphorous, sulfur, oxygen, nitrogen, manganese, silicon, aluminum, copper, nickel, etc. 4. Can be wrought, rolled, cast, and welded, but not extruded

Types of Steel

Carbon Steel

Alloy Steel - Stainless Steel

-Mild steel - HSLA Steel (high-strength low-alloy) - Weathering Steel


Stainless steel, also known as corrosion steel, is an alloy of iron, nickel and chromium. The important property of stainless steel is its high resistance to corrosion. It is tough and resistant to stains, hence, called stainless steel. It is commonly used in kitchen cutlery and cookware, medical instruments, kitchen draining boards and pipes.



Mild Steel Composition: Iron alloy with 0.3% carbon Properties: Malleable and ductile, and therefore bends fairly easily. Uses: nuts, bolts, screws, tubes etc. • If mild steel is coated in tin it is called ‘Tin plate’. • If mild steel is coated in zinc it is called ‘Galvanised sheet’. • If mild steel is coated in lead it is called ‘Terne sheet’.

Methods of Identification Appearance: Bright drawn mild steel has a smooth, bright surface;black, mild steel is covered with a blue-grey oxide.

Dropping: Gives out a ringing note Grinding: Gives off a shower of long white sparks Effect of Heating: Slightly tougher but little change


2.

Tool Steel / cast steel / carbon steel

Composition: Iron alloy with 0.5%-1.5% carbon Properties: Tough rather than hard, and fairly ductile. Uses: Springs and most tools such as hammer heads, drills, chisels, shears etc . 

Methods of Identification Appearance: Has a smooth skin of black oxide Dropping: Gives out a high ringing note Grinding: Moderate number of red sparks Effect of Heating: Becomes hard and brittle



Variety in colour, texture and surface


Processing Have all your processing, warehousing and shipping done in one place. We will pick up and store your steel, process it when you want it, the way you want it, and then deliver it on time using our dedicated truck fleet or rail service. You can also count on getting the kind of quality that will satisfy your customers' most stringent demands. You eliminate extra shipping costs, reduce paperwork and administrative hassles, cut delivery time to your customers, come out ahead of your competition and chalk up higher profits.

PICKLING

SLITTING

LEVELING

ANNEALING

TEMPER ROLLING

COLD ROLLING


Plasticity is the ability of a material to deform permanently without breaking or rupturing. This prop- erty is the opposite of strength. By careful alloying of metals, the combination of plasticity and strength is used to manufacture large structural mem bers. For example, should a member of a bridge structure become overloaded, plasticity allows the overloa ded member to flow allowing the distribution of the load to other parts of the bridge structure


Brittleness is the opposite of the property of plastic- ity. A brittle metal is one that breaks or shatters before it deforms. White cast iron and glass are good examples of brittle material. Generally, brittle metals are high in compressive strength but low in tensile strength. As an example, you would not choose cast iron for fabricating support beams in a bridge .


Malleability is the property that enables a material to deform by compres- sive forces without developing defects. A malleable material is one that can be stamped, hammered, forged, pressed, or rolled into thin sheets.


Ductility is the property that enables a material to stretch, bend, or twist without cracking or breaking. This property makes it possible for a material to be drawn out into a thin wire.


Corrosion resistance, although not a mechanical property, is important in the discussion of metals. Corrosion resistance is the property of a metal that gives it the ability to withstand attacks from atmospheric,chemical, or electrochemical conditio ns. Corrosion,sometimes cal led oxidation, is illustrated by the rusting of iron.


The metals that Steelworkers work with are divided into two general classifications: ferrous and nonferrous. Ferrous metals are those composed primarily of iron and iron alloys. Nonferrous metals are those composed pri- marily of some element or elements other than iron. Nonferrous metals or alloys sometimes contain a small amount of iron as an alloying element or as an impurity.


Of all the different metals and materials that we use in our trade, steel is by far the most important. When steel was developed, it revolutionized the American iron industry. With it came skyscrapers, stronger and longer bridges, and railroad tracks that did not collapse. Steel is manufactured from pig iron by decreasing the amount of carbon and other impurities and adding specific amounts of alloying elements. Do not confuse steel with the two general classes of iron: cast iron (greater than 2% carbon) and pure iron (less than 0.15% carbon). In steel manufacturing, con- trolled amounts of alloying elements are added during the molten stage to produce the desired composition. The composition of a steel is determined by its applica-tion and the specifications that were developed by the following: American Society for Testing and Materials (ASTM), the American Society of Mechanical Engi- neers (ASME), the Society of Automotive Engineers (SAE), and the American Iron and Steel Institute (AISI). Carbon steel is a term applied to a broad range of steel that falls between the commercially pure ingot iron and the cast irons. This range of carbon steel may be classified into four groups. Low-Carbon Steel . . . . . . . . 0.05% to 0.30% carbon Medium-Carbon Steel . . . . . . 0.30% to 0.45% carbon High-Carbon Steel . . . . . . . . 0.45% to 0.75% carbon Very High-Carbon Steel . . . . . 0.75% to 1.70% carbon


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Steel in this clssification is tough and ductile, easily machined, formed, and welded. It does not respond to any form of heat treating, except case hardening.


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These steels are strong and hard built be welded or worked as easily as low-carbon steels. They are used for crane, hooks, axles , shafts, setscrews, and co on.


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Steel in these classes respond well to heat treatment and can be welded. When welding, spe- cial electrodes must be used along with preheating and stressrelieving procedures to prevent cracks in the weld areas. These steels are used for dies, cutting tools, mill tools, railroad car wheels, chisels, knives, and so on.


A special low- carbon steel, containing specific small amounts of alloying elements, that is quenched and tempered to get a yield strength of greater than 50,000 psi and tensile strengths of 70,000 to 120,000 psi. Structural members made from these highstrength steels may have smaller cross-sectional areas than common structural steels and still have equal or greater strength. Additionally, these steels are normally more corrosion- and abrasion- resistant. High-strength steels are covered by ASTM specifications.. NOTE: This type of steel is much tougher than low-carbon steels. Shearing machines for this type of steel must have twice the capacity than that required for low-carbon steels.


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This type of steel is clas- sified by the American Iron and Steel Institute (AISI) into two general series named the 200300 series and 400 series. Each series includes several types of steel with different characteristics. The 200-300 series of stainless steel is known as AUSTENITIC. This type of steel is very tough and ductile in the as-welded condition; therefore, it is ideal for welding and requires no annealing under normal atmospheric conditions. The most wellknown types of steel in this series are the 302 and 304. They are com- monly called 18-8 because they are composed of 18% chromium and 8% nickel. The chromium nic kel steels are the most widely used and are normally non magnetic. The 400 series of steel is subdivided according to their crystalline structure into two general groups. One group is known as FERRITIC CHROMIUM and the other group as MARTENSITIC CHROMIUM.


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