Because carbon steel is an alloy hardened by the carbon content, how the steel is used depends on how much carbon it contains. For example, steel made with low carbon content can be used for wrought iron or fencing. Medium-carbon is a significant component for construction projects like bridges and buildings, while high-carbon content steel is used for coils and steel wires. Strength and durability make this steel ideal for cutting tools, saws, drills, knives, and other equipment that requires a heavy-duty cutting edge.
Stainless steel is rust-resistant because it consists of at least Any industrial facility that uses water during production will use stainless steel as a primary metal material. The corrosion-resistant properties of stainless steel make this material a natural choice for piping systems used by petrochemical, refining, solar, food processing, and other industries.
The durability and easy maintenance make stainless a logical option. For information regarding piping systems and accessories, contact APP, an essential supplier of piping accessories and support. The professionals at APP will be glad to answer any technical questions about industrial pipe designs and materials.
Hi, there! However, it is important to remember that these additional elements also impact other properties, such as toughness and ductility. Steel is one of the most common materials of the modern world — with more than 1. It is widely used in the transportation, infrastructure, building, and weapons industries.
Most large modern buildings — including skyscrapers, airports and bridges — are held up by steel structures. In the automotive industry, steel is still the principal material, although aluminum is increasingly popular.
Steel is also used in smaller items such as screws, nails and kitchen utensils. Tool steels are alloyed with tungsten and cobalt and are notable for their hardness. Tool steel can retain a sharp cutting edge and is used in axes and drills.
Maraging steel is alloyed with nickel and other elements. It has a low carbon content and is extremely strong. Maraging steel is used in rocket and missile skins, gas centrifuges for uranium enrichment, and fencing blades. Titanium is a silvered colored metal with low density and high strength. It is notable for having the highest tensile strength-to-density ratio of any metallic element. Titanium is commonly alloyed with a range of elements including iron, aluminum, and vanadium.
Titanium alloys are strong and lightweight making them ideal for automotive, aerospace, military and industrial applications. Two-thirds of all titanium metal produced is used for aircraft parts. Tungsten is a rare metal found on Earth in the form of chemical compounds. It has a metallic grey color, is brittle and hard to work. If refined to its purest form, it has a hardness that exceeds that of most steels.
Hardenability, on the other hand, refers to the amount of martensite that forms in the microstructure during cooling. Second, low-hardenability steels require rapid cooling to transform martensite, while high-hardenability steels form martensite when they're air-cooled. These hardenability characteristics are important because they help identify how much a steel will harden during welding.
Martensite in the "as quenched" condition is usually extremely brittle and, therefore, not much good to anyone. But a tempering heat treatment can increase ductility and toughness effectively with only slight to moderate reduction in strength.
Generally speaking, tempering involves reheating hardened steel to a specific temperature and holding it there for a short time before cooling. This increases toughness resistance to shock or impact loading and reduces brittleness by allowing carbon to precipitate into tiny carbide particles.
The microstructure that results is called tempered martensite. The relationship between the resulting hardness and toughness is actually a compromise that's controlled by using a specific tempering time and temperature. The higher the temperature is, the softer and tougher the steel is. I'll get into more detail on this later in this article.
Quenching and tempering improve the qualities of structural steels, pressure vessels, and even machinery. When low-alloy steels are quenched and tempered, the result is high tensile and yield strength and improved notch toughness, especially when compared to hot-rolled, normalized, or annealed steel. While precipitation hardening is an effective way to develop high strength and hardness in some steels, it's most often an aluminum-alloy application and is a little more complicated than the others, so I'll cover it in an upcoming column.
Cold working a metal deforms and stresses its crystal structures, causing the metal to work-harden. Steel mills cold-work steel by running it back and forth through rollers with the steel at a temperature below the plastic state.
This distorts the steel's grain structure, which increases its hardness and tensile strength while decreasing ductility. Sheet metal fabricators and hammer formers deal with this too. After a piece of tempered sheet metal or aluminum is worked with a hammer for a while, it begins to get hard and brittle, so you may need to temper it again to be able to keep working it without cracking or splitting it.
Solid solution hardening stresses a metal's crystal structure by adding alloying metals that don't fit easily in the base metal's crystal lattice. This added stress increases tensile strength and decreases ductility. Transformation hardening is the heat-quench-tempering heat treatment cycle addressed earlier in this article. It's used to adjust strength and ductility to meet specific application requirements. There are three steps to transformation hardening:.
By using the proper heat treatment and choosing a steel with just the right amount of carbon, you can get just about any combination of hardness and ductility to meet a specific requirement. Remember, the more pearlite and cementite that forms, the more ductile and less brittle the steel will be. Conversely, more martensite means less ductility but more hardness. One topic I've ignored up to this point is grain structure changes during precipitation hardening.
A steel's grain size depends on the austenitizing temperature.
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