{"id":21,"date":"2021-06-23T13:05:26","date_gmt":"2021-06-23T17:05:26","guid":{"rendered":"https:\/\/pressbooks.bccampus.ca\/materials\/?post_type=chapter&p=21"},"modified":"2022-03-31T14:20:43","modified_gmt":"2022-03-31T18:20:43","slug":"types-of-materials","status":"publish","type":"chapter","link":"https:\/\/pressbooks.bccampus.ca\/materials\/chapter\/types-of-materials\/","title":{"raw":"Types of Materials","rendered":"Types of Materials"},"content":{"raw":"The first way metal is classified is as [pb_glossary id=\"123\"]ferrous[\/pb_glossary] or [pb_glossary id=\"135\"]non-ferrous[\/pb_glossary]. This has to do with the amount of iron content in it. Material with more than 5% iron content is a ferrous metal, such as steel. A non-ferrous metal, like aluminum, has little or no iron in it.\r\n

Ferrous Metals<\/h1>\r\n

Mild Steel<\/h2>\r\n\"mildA common low carbon steel, mild steel is an iron [pb_glossary id=\"113\"]alloy[\/pb_glossary] containing manganese, carbon or other alloying elements. Mild steel is stronger and harder than iron, yet it is softer than tool steel. The carbon content affects the properties of steel. Higher carbon content makes the steel harder. Mild steel is common in two forms, cold rolled or hot rolled. Just like the name indicates, the material has been process either hot or cold giving different characteristics. Cold rolled is smooth and shiny, usually with a light coating of oil to prevent corrosion. Since it has been processes cold, it has been [pb_glossary id=\"147\"]work hardened[\/pb_glossary]. Hot rolled steel is black\/blueish in colour and usually has a scaly appearance.\r\n

Tool Steel<\/h2>\r\n\"steelAn [pb_glossary id=\"115\"]alloyed steel[\/pb_glossary] with a high content of carbon is called tool steel. As the name implies, tool steel is used for making tools. It is hard enough to cut standard steel and iron. The metal must be able to withstand high temperatures, high load and abrasive conditions. Because of the many applications of tools, tool steels vary in their composition.\r\n\r\n \r\n

Stainless Steel<\/h2>\r\n\"StockStainless steel contains chromium and nickel as principal alloys. Stainless steel is the only non-magnetic ferrous metal. It has high tensile strength, ductility and hardness, as well as being highly resistant to corrosion and oxidation.\r\n\r\nAvailable in many different grades and finishes, some of the common grades are: 304 for general use, 316 is a marine grade (better corrosive resistance) and 430 which is the only magnetic grade, used commonly on cooler doors.\r\n\r\nFinishes range from 1-8 (dull-mirror) with a #4 being the most common. A #4 finish has a grained appearance used as kitchen counter tops. 2B is another common finish with a cold rolled, grey appearance. A #8 finish is a polished, mirror finish used in applications like public bathroom mirrors.\r\n\"raw\r\n

Iron<\/h2>\r\nSoft, [pb_glossary id=\"133\"]malleable[\/pb_glossary] metals can be made by alloying pig iron and nickel. The resulting metal is known as nodular iron. Wrought iron and ingot iron are two other soft, easily worked and relatively weak metals.\r\n

Cast Iron<\/h3>\r\n\"crossCast iron is re-smelted pig iron and includes all of the iron and carbon alloys with more than 2% carbon and almost always, some silicon. High carbon and silicon contents give cast iron a low melting temperature and high fluidity in its liquid stage. It is easy to pour cast iron into complex molds.\r\n\r\nWhen the carbon and silicon content is in the range of 3% to 4%, the material is known as grey cast iron. Lower carbon and silicon content and rapid cooling of the casting make hard, [pb_glossary id=\"258\"]brittle[\/pb_glossary], white cast iron. White cast iron can be converted with [pb_glossary id=\"131\"]heat treatment[\/pb_glossary] to a [pb_glossary id=\"133\"]malleable[\/pb_glossary] iron that has properties similar to mild or low carbon steel. Cast iron is used for engine blocks, heads and housing assemblies.\r\n

Pig Iron<\/h3>\r\n\"picturePig iron is the basic metal obtained from iron ore.\r\n\r\nMost ferrous metals begin as pig iron. It has a very high carbon content and is cast into bars called pigs.\r\n

Non-Ferrous Metals<\/h1>\r\nAluminum and copper are two common examples of [pb_glossary id=\"135\"]non-ferrous[\/pb_glossary] metals. Non-ferrous metals are usually non-sparking and non-magnetic. They also have a common characteristic, in that the [pb_glossary id=\"137\"]oxides[\/pb_glossary] that form on non-ferrous metal tend to protect the metal, not destroy it. Meaning they may not be damaged by water (oxidation), but they will stain if allowed to sit in wet for any length of time. Always dry sheets before storing.\r\n

Aluminum<\/h2>\r\n\"stockAluminum is light weight and resistant to corrosion. It has low electrical resistance, high heat conductivity and good [pb_glossary id=\"119\"]ductility[\/pb_glossary] combined with considerable strength. Used extensively in the aeronautical industry, aluminum is also used for industrial tanks, truck and bus frames and equipment body parts. The principle ore it is made from is called bauxite, it weighs approximately 60% of same thickness of steel.\r\n\r\nThere are seven types of aluminum which have a series number to indicate the main [pb_glossary id=\"113\"]alloys[\/pb_glossary] added. If a series number is followed by an \"H\" that means it is not [pb_glossary id=\"131\"]heat treatable[\/pb_glossary] and has been [pb_glossary id=\"147\"]strain hardened[\/pb_glossary]. A number following the \"H\" such as \"H1\" indicates the degree of strain hardening. A series number followed by a \"T\" indicates its [pb_glossary id=\"141\"]temper[\/pb_glossary] has been modified but that it is heat treatable. That is, it may be [pb_glossary id=\"117\"]annealed[\/pb_glossary].\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n
Series #-Alloy<\/th>\r\nCommon Use<\/th>\r\n<\/tr>\r\n
1000-pure aluminum<\/td>\r\nToo soft for general sheet use<\/td>\r\n<\/tr>\r\n
2000-copper<\/td>\r\nAircraft skins 2024-T4<\/td>\r\n<\/tr>\r\n
3000-manganese<\/td>\r\nUtility grade-3003<\/td>\r\n<\/tr>\r\n
4000-silicon<\/td>\r\nWelding wire and architectural applications<\/td>\r\n<\/tr>\r\n
5000-magnesium<\/td>\r\nMarine grade-5052<\/td>\r\n<\/tr>\r\n
6000-magnesium and silicon<\/td>\r\nstructural shapes-6061-T4<\/td>\r\n<\/tr>\r\n
7000-zinc<\/td>\r\nHigh strength applications aircraft frames-7075<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n

Brass<\/h2>\r\n\"stockBrass is an alloy of copper and zinc. Brass is stronger than copper and is corrosive resistant, making it an ideal metal for ships' fittings, locks and condenser tubes. Standard brass, which contains 30-34% zinc, is used extensively for valves and fittings.\r\n

Bronze<\/h2>\r\nAn alloy of copper and tin commonly used in castings.\r\n

Copper<\/h2>\r\n\"stockCopper is fairly resistant to corrosion, has good tensile strength and is an excellent conductor of electricity. Copper is highly resistant to many chemicals and to corrosion from air and sea water. It should not be used in contact with oxidizing acids. Copper is very [pb_glossary id=\"133\"]malleable[\/pb_glossary] and [pb_glossary id=\"119\"]ductile[\/pb_glossary]. As it is drawn or cold worked, it will increase in [pb_glossary id=\"143\"]tensile strength[\/pb_glossary] and become less and less ductile or [pb_glossary id=\"147\"]work hardened[\/pb_glossary]. It may be [pb_glossary id=\"117\"]annealed[\/pb_glossary] after. Copper is used for water supply lines, electrical wiring and soft tubing.\r\n

Lead<\/h2>\r\n\"leadLead is a very dense, heavy metal. It has a low melting point of 327\u00b0C (620\u00b0F), making it easy to use in liquid form. Lead can be rolled into sheets, cast or bent into shapes and [pb_glossary id=\"121\"]extruded[\/pb_glossary] into pipes. However, due to its plastic nature, it is structurally weak. One of lead's most important assets is its corrosion resistance owing to a protective film of [pb_glossary id=\"137\"]oxides [\/pb_glossary] formed on its surface. Lead is often used as a coating on other metals to protect them from corrosion. Lead is also used in the construction of batteries and in solder. It is very toxic, so caution should be taken when handling lead.\r\n

Monel<\/h2>\r\nAn alloy of copper and nickel that has a high corrosive resistance.\r\n

Coated Metal<\/h1>\r\nAnother way that metal is classified is as coated or solid. A sheet metal worker will use both solid (uncoated) and coated. The coating in most cases is for corrosion protection, but can be for other purposes as well. Welding of coated sheets always should be considered carefully.\r\n

Alclad<\/h2>\r\n\"alcladSome aluminum sheets are not very corrosive resistant because of their alloying, like 2024 for example. These sheets are commonly coated in pure aluminum, called Alclad. Aircraft and aluminum RV\u2019s use these sheets. Usually covered on a clear plastic for protection, Alclad aluminum goes through much more involved processing, making it much more expensive.\r\n

Galvanization<\/h2>\r\n\"galvanizedGalvanized sheet metal is when the metal has been coated in zinc. This is the most common coating used in sheet metal. This can be done in 2 different processes: hot dipping or electroplating. Sheets that have a \u201cspackled\u201d and smooth appearance have been hot dipped and are commonly used for ductwork. Sheets that have been electroplated have a chalky, dull-grey appearance. Also known as satin coat, paint bond, or wipecoat, these sheets are used when painting is required. The coating not only acts as corrosion resistance, but because of the finish, it will accept paint easily with no scuffing or priming.\r\n

Pre-painted<\/h2>\r\n\"stockPre-painted material is commonly used in architectural sheet metal. They come in an almost endless array of different colour and finishes, even wood grain. Vinyl coating may also be included in this category.\r\n

Tinplate and Terneplate<\/h2>\r\nTinplate is a sheet of steel coated in pure tin. It was commonly used in the past. Now, tinplate is used in tin cans and other food products for its corrosive resistance and sanitary qualities. Terneplate is a coating of tin and lead alloyed together.\r\n\r\n[caption id=\"attachment_176\" align=\"aligncenter\" width=\"512\"]\"picture A tinplate bath, Europe, 1801-1900. During the 1800s, personal hygiene and cleanliness were increasingly considered one way to improve health and prevent the spread of disease. However, very few people had a piped domestic water supply. At best, many people would rely on a bath such as this one, perhaps set up in front of the fire and filled with buckets of water heated from the stove.[\/caption]\r\n

Media Attributions<\/h3>\r\n