Allegheny Technologies Inc. (ATI) posted record sales in the second quarter thanks to strong demand for its aerospace, exotic alloy, engineered and specialty steel products.

Net income for the three months ended June 30 more than tripled to $91.7 million compared with the same period last year on sales that rose 39.9 percent to $904.2 million. For the first half of the year, the company posted net income of $152.7 million in contrast to a net loss of $23.8 million a year earlier on a 45.7-percent increase in sales to $1.78 billion.

"We remain confident about the prospects for ATI and continue to build a foundation for further growth," said L. Patrick Hassey, chairman, president and chief executive officer of the Pittsburgh-based company.

While demand was strong for nickel-based alloys, specialty steels and titanium products from the oil and gas, electrical energy, aerospace and chemical processing markets, the company said inventory management actions at service centers and in the supply chain resulted in reduced shipments of stainless sheet and engineered strip.

Hassey said he believes ATI's second-half earnings performance will be similar to the first half, although third-quarter earnings are likely to be lower than the fourth quarter due to normal seasonal slowing in the flat-rolled products segment.

"We expect to see reduced shipments of stainless commodity products through most of the third quarter from continuing inventory management actions throughout the supply chain," he said. "We are taking action in our flat-rolled products business to reduce inventory and are encouraged by published reports that many global stainless steel producers also are adjusting their production to market demand."

The conversation usually begins like this: "Hey, this is Joe from Joe's Machine Shop. We have a job in here and the customer wants us to have some kind of passivate coating something or other. Do you guys do that? How thick is that stuff? Is that like plating, paint or what? What color is it? How much tolerance should I allow for it?" The opening statement usually ends with a phrase like: "I don't even know why they need it. What is the point of using stainless steel if you are going to put some kind of coating on it anyway?"

Joe is not the exception. Many machine shops, purchasing agents and engineers are somewhat in the dark when it comes to the relationship between corrosion resistant (stainless) steel and chemical passivation. Even among the finishing community, there is some disagreement about the theory behind the process of chemical passivation. Some believe it is effective because it is a cleaning process. Others credit the enhanced corrosion resistance properties to the thin, transparent oxide film resulting from chemical passivation.

Regardless, the bottom line is that it works. Verification tests, including copper sulfate immersion, and accelerated corrosion tests, such as salt spray, high humidity and water immersion, undisputedly confirm the effectiveness of chemical passivation. Advanced material engineers in aerospace, electronics, medical and similar high-tech industries have used chemical passivation for years. The applications demand the maximum performance from components manufactured from corrosion-resistant steels, and they realize that passivation is one of the most effective methods of achieving these results.
According to ASTM A38O, passivation is "the removal of exogenous iron or iron compounds from the surface of stainless steel by means of a chemical dissolution, most typically by a treatment with an acid solution that will remove the surface contamination, but will not significantly affect the stainless steel itself." In addition, it also describes passivation as "the chemical treatment of stainless steel with a mild oxidant, such as a nitric acid solution, for the purpose of enhancing the spontaneous formation of the protective passive film."

Aerodyne Ulbrich Alloys (South Windsor, Connecticut) has a new online store for its titanium alloy, nickel alloy, and stainless steel bar, cut plate and sheet products. It offers pre-processed and packaged materials and small order size options to buyers who prefer online buying. The site is said to contain hard-to-find grades in a variety of dimensions. The store is at www.aerodynedirect.com.

Russia produced 40.51 million tonnes of ferrous metal roll in the first ten months of 2002, up 3.6 percent year-on- year, the State Statistics Committee has said.

Sheet production grew 7 percent to 17.32 million tons, of which 5.62 million tons of cold-rolled sheet, and sections and bars grew 1.1 percent to 22.8 million tons.

Russia produced 38.25 million tons of pig iron, including blast- furnace alloys, up 1.9 percent year-on- year. Crude steel production grew 0.6 percent to 49.71 million tons.

The stainless steel industry is following a similar path traveled by the carbon steel industry, and specialty steel demand actually was hit harder than carbon in the current economic environment, according to an industry analyst.

Stainless and specialty steel had higher import penetration rates than carbon steel, and stainless flat-rolled price recovery in 2002 was more modest than carbon, Paul Lowrey, managing partner of SteelBase Partners, said at AMM 's 17th Stainless and Alloys Conference here.

Lowrey said that demand for specialty steel slipped 17 percent compared with the 2000 peak, while demand for carbon steel fell 11 percent in the same comparison.

He contended that the carbon steel industry had come to the end of the road it was on. He said the Section 201 remedies gave the industry some breathing room, while Chapter 11 and 7 restructuring, consolidation, the collapse of asset prices, some steel loan assistance as well as Cleveland-based International Steel Group Inc. arising as a new entrepreneurial driver were all factors in the industry's overall restructuring.
* A demand rebound is unlikely soon.

* There could be a core bankruptcy soon.

* Labor/legacy costs are becoming an issue.

* New ownership could emerge to stir things up.

Lowrey said that while the renegotiation of labor contracts had changed the landscape of the integrated industry, he was not sure how that would come into play in the stainless market.

"Keep in mind, it took the Chapter 7 of LTV Corp to bring that all about," Lowrey told conference attendees.

Ed Blot, president of Ed Blot & Associates Inc., Canton, Ohio, said everyone was trying to address the labor/legacy issues. Blot, who discussed trade issues related to the stainless industry, said U.S. producer shipments had declined during the past three years, except for rod. He added that import penetration had not declined significantly during the same time span, except for rod products.

While the stainless steel industry continues to suffer from weak worldwide economies, excess capacity and unfavorable cost structures, among other factors, the situation might not be as dire as some people make it out to be, according to one industry analyst.

Christopher Plummer, managing director of Metal Strategies Inc., West Chester, Pa., said there were some variables in place that pointed to business having the chance to be better for those in the stainless industry.

Plummer pointed to mortgage-refinancing gains; a market poised to start seeing improved capital spending; a government spending spree; the potential for further economic stimulus from President Bush's expected tax cut; and sharply reduced oil prices.

An alloy of iron with small amounts of carbon; widely used in construction; mechanical properties can be varied over a wide range.

Exports from India

The iron and steel sector in India was set up to meet her domestic needs and support infrastructure development of the nation. Iron and steel exports from India started after 1964, the first time India's supply dominated her domestic needs. Though the Indian exports are quite vulnerable to domestic demand conditions, the export market has been doing reasonably well in the past few years, with FY03 seeing an increase of more than 100% over the previous year. The increase in exports to Asia (approx. 227%) and America (105%) has contributed to this massive growth. In spite of the fact that India has done well, it still faces stiff competition, holding the twenty-fifth rank in the global export markets for iron and steel and the twentieth position for iron and steel articles in FY03. Also, the share of India is very low in most of its major markets (around 3%).

The largest importer of iron and steel from India is China and that for iron and steel articles is USA. It is interesting to note that whereas China holds the top position in the Indian iron and steel export markets, it doesn't even figure in the top fifteen destinations for iron and steel articles exports from India.

Observers

In India, apparent steel consumption increased by 6.5% in 1999 and a further increase of 7% is expected in 2000. Activity in steel consuming sectors like consumer durable goods, automobile and industrial machinery are growing a rates between 11.5 and 13.6% this year, while activity in the construction sector, which is the single largest consumer of all steel products, is expected to grow by 7%. Crude steel production that increased by 10.8% in 1999 should continue to grow another 10% in 2000. Steel exports should increase by 15%, and. total steel imports are expected to increase by 10%.

Global Market

The iron and steel sector is highly diversified, with products ranging from basic raw materials to semi-finished and finished products. The present study integrates on two broad categories- iron and steel and iron and steel articles. Iron and steel includes a wide category of products such as alloys, bars and rods, flat-rolled products whereas iron and steel articles mostly comprises of consumer goods like tables, tubes, pipes, track etc. Germany holds the top position for the aggregated iron and steel products (iron and steel and iron and steel articles) worldwide as a supplier. The total size of the world market for iron and steel stood at US$ 117.5 bn for FY03. The market is relatively concentrated with the top ten exporters contributing for more than half (57%) of the entire exports. The major exporters have been Germany, Japan and France with a share of 10.1%, 9.4% and 7% respectively.

The total size of the world market for iron and steel articles for FY03 was valued at US$ 88.6 bn. Germany has been the leading exporter (13.1%) followed by USA (11.6%) and China (9.2%). The market for iron and steel articles is more concentrated with the top exporters contributing around 66.6% of the total exports. The major developed countries have been dominating the world market for both the categories, indicating that higher capital availability is crucial for this sector's development.

Future Prospects

The sector has been facing tariff and non-tariff barriers (in the form of anti-dumping investigations, safeguard measures etc.) from various countries. USA and EU are the two regions where the iron and steel trade has seen the most persistent non-tariff barriers. Mexico and Venezuela have raised tariffs as high as 25% and 35% respectively. In such times when the exports are being hit, the cheap imports of seconds and defectives have adversely affected our domestic sector.

However, the medium to long term prospects for the Indian iron and steel export sector look promising. USA repealed the safeguard measures on steel imports as per a WTO ruling. Further, China has emerged as the most vibrant economy for both domestic production as well as consumption. With a high growth rate, China is expected to contribute around 58% in the anticipated global consumption in the year 2004. The increase in consumption in China can be attributed to the infrastructure developments, the spurt coming in part from the next Olympic games, to be held at Beijing. These are opportunities that India should look to capitalise on. India should also capitalise on its advantage as a supplier of galvanised products. The galvanised products are value added products that are mainly used for roofing, grain storage purposes and technical goods like AC, automobiles etc, and India has a dominant position in the world market for this product.

With the prices firming up and the global economy on a gradual recovery, the Indian export market is expected to expand soon. Given the cheap availability of inputs (raw materials, manpower) and the various incentive schemes, the Indian exporters have immense opportunities not only to increase their share in the existing markets but also to diversify into other markets. Iran, Vietnam (for iron and steel) and Spain, Indonesia (for iron and steel articles) registered high growth rates during FY98-FY03, exceeding 80% and 40% respectively, indicating other possible potential market destinations that await India's exploration.

There are a large number of stainless steels produced. Corrosion resistance, physical properties, and mechanical properties are generally among the properties considered when selecting stainless steel for an application. A more detailed list of selection criteria is listed below:

* Corrosion resistance
*Resistance to oxidation and sulfidation
* Toughness
*Cryogenic strength
*Resistance to abrasion and erosion
*Resistance to galling and seizing
*Surface finish
*Magnetic properties
*Retention of cutting edge

* Ambient strength
* Ductility
* Elevated temperature strength
* Suitability for intended cleaning procedures
* Stability of properties in service
* Thermal conductivity
* Electrical resistivity
* Suitability for intended fabrication techniques

Corrosion resistance is commonly the most significant characteristic of a stainless steel, but can also be the most difficult to assess for a specific application. General corrosion resistance is comparatively easy to determine, but real environments are usually more complex. An evaluation of other pertinent variables such as fluid velocity, stagnation, turbulence, galvanic couples, welds, crevices, deposits, impurities, variation in temperature, and variation from planned operating chemistry among others issues need to be factored in to selecting the proper stainless steel for a specific environment.

AMC can provide engineering services to determine how to optimize the selection of stainless steel for your application. Our engineering analysis can reduce overall costs, minimize service problems, and optimize fabrication of your structure.

Stainless Steels are iron-base alloys containing Chromium. Stainless steels usually contain less than 30% Cr and more than 50% Fe. They attain their stainless characteristics because of the formation of an invisible and adherent chromium-rich oxide surface film. This oxide establishes on the surface and heals itself in the presence of oxygen. Some other alloying elements added to enhance specific characteristics include nickel, molybdenum, copper, titanium, aluminum, silicon, niobium, and nitrogen. Carbon is usually present in amounts ranging from less than 0.03% to over 1.0% in certain martensitic grades. Corrosion resistance and mechanical properties are commonly the principal factors in selecting a grade of stainless steel for a given application.

Stainless steels are commonly divided into five groups:

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Martensitic stainless steels
*

Ferritic stainless steels
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Austenitic stainless steels
*

Duplex (ferritic-austenitic) stainless steels
*

Precipitation-hardening stainless steels.

Martensitic stainless steels are essentially alloys of chromium and carbon that possess a martensitic crystal structure in the hardened condition. They are ferromagnetic, hardenable by heat treatments, and are usually less resistant to corrosion than some other grades of stainless steel. Chromium content usually does not exceed 18%, while carbon content may exceed 1.0 %. The chromium and carbon contents are adjusted to ensure a martensitic structure after hardening. Excess carbides may be present to enhance wear resistance or as in the case of knife blades, to maintain cutting edges.

Ferritic stainless steels are chromium containing alloys with Ferritic, body centered cubic (bcc) crystal structures. Chromium content is typically less than 30%. The ferritic stainless steels are ferromagnetic. They may have good ductility and formability, but high-temperature mechanical properties are relatively inferior to the austenitic stainless steels. Toughness is limited at low temperatures and in heavy sections.

Austenitic stainless steels have a austenitic, face centered cubic (fcc) crystal structure. Austenite is formed through the generous use of austenitizing elements such as nickel, manganese, and nitrogen. Austenitic stainless steels are effectively nonmagnetic in the annealed condition and can be hardened only by cold working. Some ferromagnetism may be noticed due to cold working or welding. They typically have reasonable cryogenic and high temperature strength properties. Chromium content typically is in the range of 16 to 26%; nickel content is commonly less than 35%.

Duplex stainless steels are a mixture of bcc ferrite and fcc austenite crystal structures. The percentage each phase is a dependent on the composition and heat treatment. Most Duplex stainless steels are intended to contain around equal amounts of ferrite and austenite phases in the annealed condition. The primary alloying elements are chromium and nickel. Duplex stainless steels generally have similar corrosion resistance to austenitic alloys except they typically have better stress corrosion cracking resistance. Duplex stainless steels also generally have greater tensile and yield strengths, but poorer toughness than austenitic stainless steels.

Precipitation hardening stainless steels are chromium-nickel alloys. Precipitation-hardening stainless steels may be either austenitic or martensitic in the annealed condition. In most cases, precipitation hardening stainless steels attain high strength by precipitation hardening of the martensitic structure.

Steels are among the most commonly used alloys. The complexity of steel alloys is fairly significant. Not all effects of the varying elements are included. The following text gives an overview of some of the effects of various alloying elements. Additional research should be performed prior to making any design or engineering conclusions.

Carbon has a major effect on steel properties. Carbon is the primary hardening element in steel. Hardness and tensile strength increases as carbon content increases up to about 0.85% C as shown in the figure above. Ductility and weldability decrease with increasing carbon.

Manganese is generally beneficial to surface quality especially in resulfurized steels. Manganese contributes to strength and hardness, but less than carbon. The increase in strength is dependent upon the carbon content. Increasing the manganese content decreases ductility and weldability, but less than carbon. Manganese has a significant effect on the hardenability of steel.

Phosphorus increases strength and hardness and decreases ductility and notch impact toughness of steel. The adverse effects on ductility and toughness are greater in quenched and tempered higher-carbon steels. Phosphorous levels are normally controlled to low levels. Higher phosphorus is specified in low-carbon free-machining steels to improve machinability.

Sulfur decreases ductility and notch impact toughness especially in the transverse direction. Weldability decreases with increasing sulfur content. Sulfur is found primarily in the form of sulfide inclusions. Sulfur levels are normally controlled to low levels. The only exception is free-machining steels, where sulfur is added to improve machinability.

Silicon is one of the principal deoxidizers used in steelmaking. Silicon is less effective than manganese in increasing as-rolled strength and hardness. In low-carbon steels, silicon is generally detrimental to surface quality.

Copper in significant amounts is detrimental to hot-working steels. Copper negatively affects forge welding, but does not seriously affect arc or oxyacetylene welding. Copper can be detrimental to surface quality. Copper is beneficial to atmospheric corrosion resistance when present in amounts exceeding 0.20%. Weathering steels are sold having greater than 0.20% Copper.

Lead is virtually insoluble in liquid or solid steel. However, lead is sometimes added to carbon and alloy steels by means of mechanical dispersion during pouring to improve the machinability.

Boron is added to fully killed steel to improve hardenability. Boron-treated steels are produced to a range of 0.0005 to 0.003%. Whenever boron is substituted in part for other alloys, it should be done only with hardenability in mind because the lowered alloy content may be harmful for some applications.

Boron is a potent alloying element in steel. A very small amount of boron (about 0.001%) has a strong effect on hardenability. Boron steels are generally produced within a range of 0.0005 to 0.003%. Boron is most effective in lower carbon steels.

Chromium is commonly added to steel to increase corrosion resistance and oxidation resistance, to increase hardenability, or to improve high-temperature strength. As a hardening element, Chromium is frequently used with a toughening element such as nickel to produce superior mechanical properties. At higher temperatures, chromium contributes increased strength. Chromium is a strong carbide former. Complex chromium-iron carbides go into solution in austenite slowly; therefore, sufficient heating time must be allowed for prior to quenching.

Nickel is a ferrite strengthener. Nickel does not form carbides in steel. It remains in solution in ferrite, strengthening and toughening the ferrite phase. Nickel increases the hardenability and impact strength of steels.

Molybdenum increases the hardenability of steel. Molybdenum may produce secondary hardening during the tempering of quenched steels. It enhances the creep strength of low-alloy steels at elevated temperatures.

Aluminum is widely used as a deoxidizer. Aluminum can control austenite grain growth in reheated steels and is therefore added to control grain size. Aluminum is the most effective alloy in controlling grain growth prior to quenching. Titanium, zirconium, and vanadium are also valuable grain growth inhibitors, but there carbides are difficult to dissolve into solution in austenite.

Zirconium can be added to killed high-strength low-alloy steels to achieve improvements in inclusion characteristics. Zirconium causes sulfide inclusions to be globular rather than elongated thus improving toughness and ductility in transverse bending.

Niobium (Columbium) increases the yield strength and, to a lesser degree, the tensile strength of carbon steel. The addition of small amounts of Niobium can significantly increase the yield strength of steels. Niobium can also have a moderate precipitation strengthening effect. Its main contributions are to form precipitates above the transformation temperature, and to retard the recrystallization of austenite, thus promoting a fine-grain microstructure having improved strength and toughness.

Titanium is used to retard grain growth and thus improve toughness. Titanium is also used to achieve improvements in inclusion characteristics. Titanium causes sulfide inclusions to be globular rather than elongated thus improving toughness and ductility in transverse bending.

Vanadium increases the yield strength and the tensile strength of carbon steel. The addition of small amounts of Vanadium can significantly increase the strength of steels. Vanadium is one of the primary contributors to precipitation strengthening in microalloyed steels. When thermomechanical processing is properly controlled the ferrite grain size is refined and there is a corresponding increase in toughness. The impact transition temperature also increases when vanadium is added.

All microalloy steels contain small concentrations of one or more strong carbide and nitride forming elements. Vanadium, niobium, and titanium combine preferentially with carbon and/or nitrogen to form a fine dispersion of precipitated particles in the steel matrix

Steel Alloys can be divided into five groups

* Carbon Steels

* High Strength Low Alloy Steels

* Quenched and Tempered Steels

* Heat Treatable Low Alloy Steels

* Chromium-Molybdenum Steels

Steels are readily available in various product forms. The American Iron and Steel Institute defines carbon steel as follows:

Steel is considered to be carbon steel when no minimum content is specified or required for chromium, cobalt, columbium [niobium], molybdenum, nickel, titanium, tungsten, vanadium or zirconium, or any other element to be added to obtain a desired alloying effect; when the specified minimum for copper does not exceed 0.40 per cent; or when the maximum content specified for any of the following elements does not exceed the percentages noted: manganese 1.65, silicon 0.60, copper 0.60. Carbon steels are normally classified as shown below.

Low-carbon steels contain up to 0.30 weight percent C. The largest category of this class of steel is flat-rolled products (sheet or strip) usually in the cold-rolled and annealed condition. The carbon content for these high-formability steels is very low, less than 0.10 weight percent C, with up to 0.4 weight percent Mn. For rolled steel structural plates and sections, the carbon content may be increased to approximately 0.30 weight percent, with higher manganese up to 1.5 weight percent.

Medium-carbon steels are similar to low-carbon steels except that the carbon ranges from 0.30 to 0.60 weight percent and the manganese from 0.60 to 1.65 weight percent. Increasing the carbon content to approximately 0.5 weight percent with an accompanying increase in manganese allows medium-carbon steels to be used in the quenched and tempered condition.

High-carbon steels contain from 0.60 to 1.00 weight percent C with manganese contents ranging from 0.30 to 0.90weight percent.

High-strength low-alloy (HSLA) steels, or microalloyed steels, are designed to provide better mechanical properties than conventional carbon steels. They are designed to meet specific mechanical properties rather than a chemical composition. The chemical composition of a specific HSLA steel may vary for different product thickness to meet mechanical property requirements. The HSLA steels have low carbon contents (0.50 to ~0.25 weight percent C) in order to produce adequate formability and weldability, and they have manganese contents up to 2.0 weight percent. Small quantities of chromium, nickel, molybdenum, copper, nitrogen, vanadium, niobium, titanium, and zirconium are used in various combinations.

Many metals and alloys have high densities and are used in applications which require a high mass-to-volume ratio.

Some metal alloys, such as those based on Aluminum, have low densities and are used in aerospace applications for fuel economy.

Many metal alloys also have high fracture toughness, which means they can withstand impact and are durable.

Pure metals are elements which comes from a particular area of the periodic table. Examples of pure metals include copper in electrical wires and aluminum in cooking foil and beverage cans.

Metal Alloys contain more than one metallic element. Their properties can be changed by changing the elements present in the alloy.

Examples of metal alloys include stainless steel which is an alloy of iron, nickel, and chromium; and gold jewelry which usually contains an alloy of gold and nickel.

Metals are elements that generally have good electrical and thermal conductivity.

Many metals have high strength, high stiffness, and have good ductility.

Some metals, such as iron, cobalt and nickel are magnetic.

At extremely low temperatures, some metals and intermetallic compounds become superconductors.

HSLA steel (high strength low alloy steel) is a type of steel alloy that provides many benefits over regular steel alloys. In general, HSLA alloys are much stronger and tougher than ordinary plain carbon steels. They are used in cars, trucks, cranes, bridges and other structures that are designed to handle a lot of stress, often at very low temperatures.


HSLA steels are so called because they only contain a very small percentage of carbon. A typical HSLA steel may contain 0.15% carbon, 1.65% manganese and low levels (under 0.035%) of phosphorous and sulphur[1]. It may also contain small amounts of copper, nickel, niobium, nitrogen, vandium, chromium, molybdenum, silicon or zirconium. HSLAs are therefor also referred to as 'microalloyed', as they are indeed alloyed in extremely small amounts by comparison to other main commercial alloy steels. As little as 0.10% niobium and vanadium can have profound effects on the mechanical properties of a 0.1%C, 1.3% Mn steel. These added elements are intended to utterly alter the microstructure of plain carbon steels, which is usually a ferrite-pearlite aggregate, to produce a very fine dispersion of alloy carbides in an almost pure ferrite. This eliminates the toughness-reducing effect of a pearlitic volume fraction, yet maintains and even increases the material's strength by precipitation strengthening and by refining the grain size, which in the case of ferrite increases yield strength by 50% for every halving of the mean grain diameter.

Alloying elements are added to basic steels to enhance corrosion resistance, hardness, toughness and processibility.

Carbon is the principal hardener in steel. The more carbon that is added (up to 1.2%), the harder it gets. Higher amounts of carbons create high levels of cementite (Fe3C) and go under various names such as white iron, etc.

Phosphorus and Sulfur are present in all steels, usually as impurities, but they are sometimes added in controlled amounts for easier machining.

Molybdenum is one of the most important additives. Molybdenum adds toughness and increases corrosion resistance to withstand industrial chemicals and solvents and inhibits pitting caused by chlorides. Molybdenum also lengthens the quench time of a steel, so that a good, stress-free martensitic structure can be formed. Molybdenum also inhibits grain growth.

Cobalt scissors come in two types. Forged Steel and Powder or Sintered Metal. The powdered metals give the maximum cobalt benefit, but are VERY susceptible to breaking. Never set or bend a cobalt scissor, unless you enjoy buying a new one. The powder metal cobalt alloy demonstrates outstanding mechanical properties and cutting performance. Powder metal cobalt scissors are usually composed of a 50% Co (Cobalt) - 28.7% Fe (Iron) -20% W (Tungsten) - 1.3% C (Carbon) alloy. These alloys attain an un-tempered maximum value of 66 to 67 Rc. Forged Cobalt tools are much tougher than sintered metals, but seldom have more than 10% cobalt in them, making them softer with Rockwells around 58Rc.

Manganese contributes to strength and hardness. The amount of increase is dependent on the amount of carbon present. The more carbon in a steel, the higher the effect of manganese. Manganese is beneficial for the surface finish of a part, especially if the steel is high in sulfur.

Phosphorus increases strength and hardness, but at the sacrifice of ductility and impact toughness, if added in too great a quantity.

Sulfur is detrimental to surface finish in high quantities, but improves machinability.

Silicon is a principal deoxidizer used in steel making. It also increases strength and hardness.

Chromium protects against corrosion and adds heat resistance. Decreases strength and hardness. Must be at about a 18:1 ratio with carbon, since the carbon can take from the alloy about 17 times its own weight of chromium to form carbides. This chromium in the form of carbides is of little use for resisting corrosion.

Carbon Steel - Steel is considered carbon steel, when no minimum content is specified or required of chromium, molybdenum, vanadium, nickel, tungsten or any other element added. The following elements do not exceed 1.65% manganese, 0.60% silicon, or 0.60% copper.

Vanadium adds toughness and fatigue resistance.

Nickel improves corrosion resistance and toughness. Allows higher chromium alloys to fully harden. Types 414 and 431 are the most corrosive resistant of the martensitic steels.

A FULL range of copper-cored steel alloys for making glass-to-metal seals used in electrical switches and motor controls, where size and conductivity are important, is available from Anomet Products.
Copper-cored steel alloys combine the conductivity of copper with low thermal expansion materials and feature a complete metallurgical bond which provides total hermetic sealing between the metals.

Permitting the use of smaller and lighter pins, they are offered in 0.5mm to 10mm sizes with 2:1 and 3:1 ratios of the alloy to the copper core.

Supplied on spools, reels, or wrapped coils, they are available as Alloy 52 Nickel-Iron, Kovar Nickel-Iron-Cobalt, Alloy 42-6 Nickel-Chromium, and Alloy 446SS Iron-Chromium, each with a copper core (100% IACS minimum conductivity).

Any customer specified temper is offered, with dimensional tolerances to ±.01mm, depending upon diameter.

Anomet alloys are priced according to type and quantity. Literature and evaluation samples are available upon request.

Alloy steels were known from antiquity, being nickel-rich iron from meteorites hot-worked into useful products. In a modern sense, alloy steels have been made since the invention of furnaces capable of melting iron, into which other metals could be thrown and mixed.

Historic types

* Damascus steel, which was famous in ancient times for its durability and ability to hold an edge, was created from a number of different materials (some only in traces), essentially a complicated alloy with iron as main component.
* Blister steel - steel produced by the cementation process
* Crucible steel - steel produced by Benjamin Huntsman's crucible technique
* Styrian Steel, also called 'German steel' or 'Cullen steel' (being traded through Cologne) was made in Styria in Austria by fining cast iron from certain manganese-rich ores.
* Shear steel was blister steel that was broken up, faggotted, heated and welded to produce a more homogeneous product.

Contemporary Steel

* Carbon steel, of which mild steel is one type.
* Stainless steels and surgical stainless steels contain a minimum of 10.5% chromium, often combined with nickel, to resist corrosion (rust). Some stainless steels are nonmagnetic.
* Tool steels
* HSLA steel (high strength, low alloy)
* Advanced High Strength Steels
o Complex Phase Steel
o Dual Phase Steel
o TRIP steel
o TWIP steel
o Maraging steel
* Ferrous superalloys
* Hatfield steel or Manganese steel, this contains 12-14% manganese which when abraded forms an incredibly hard skin which resists wearing. Some examples are tank tracks, bulldozer blade edges and cutting blades on the jaws of life.

Though not an alloy, there exists also galvanized steel, which is steel that has gone through the chemical process of being hot-dipped or electroplated in zinc for protection against rust. Finished steel is steel that can be sold without further work or treatment.

Production methods

* Crucible technique - the original steel making technique, developed in India as wootz, used in the Middle East as Damascus steel.
* Cementation process used to convert bars of wrought iron into blister steel. This was the main process used in England from the early 17th century.
* The more recent version of the crucible technique was independently redeveloped in Sheffield by Benjamin Huntsman in c.1740, and Pavel Anosov in Russia in 1837. Huntsman's raw material was blister steel.
* Bessemer process, the first large-scale steel production process for mild steel.
* Puddling
* The Siemens-Martin process, using an Open hearth furnace
* Basic oxygen steelmaking
* Electric arc furnace a form of secondary steelmaking from scrap, though the process can also use direct-reduced iron

Stainless steel alloys are austenitic, ferritic, martensitic, precipitation hardened, and duplex metals that are available in a wide variety of grades, shapes, and sizes. Austenitic stainless steels have excellent corrosion resistance, unusually good formability, and increased strength due to cold working. They are non-magnetic or only slightly magnetic. Two hundred (200) series austenitic stainless steels contain chromium, nickel, and manganese. Three hundred (300) series austenitic stainless steels contain chromium and nickel. Ferritic stainless steels are straight-chromium, 400 series metals that cannot be hardened by heat treatment, and only moderately hardened by cold working. They are magnetic, have good ductility, and resist corrosion and oxidation. Martensitic stainless steels, another type of straight-chromium 400 series metals, are magnetic, fairly ductile, and resist corrosion in mild environments. Some products can be heated to tensile strengths that exceed 200,000 psi (1379 MPa). Precipitation hardened (PH) stainless steels are chromium-nickel metals, some of which contain alloying elements such as copper or aluminum. They can be hardened by solution treating and aged to high strength. Duplex stainless steel alloys have improved mechanical properties and consist of a combination of ferritic and austenitic phases.

Many stainless steel alloys meet the compositional standards of the Unified Numbering System (UNS), a specification established by the American Society for Testing and Materials (ASTM), the Society of Automotive Engineers (SAE), and metal trade associations such as the American Iron and Steel Institute (AISI). The UNS assigns metals and alloys a lettered prefix and a five-digit number. Stainless steel alloys belong to the UNS S category and have designations such as UNS S20100. AISI grades are another common specification for stainless steel alloys. Other standards include casting grades, European Norm (EN), American Society of Mechanical Engineers (ASME) standards, and U.S. military specifications (MIL-SPEC). QQ and QQS prefixes are used to designate specific MIL-SPEC metals. Grades with low carbon levels (L or S grades) provide improved weldability and corrosion resistance. Grades that contain superalloys, tool steels, clad or bimetal materials, or that feature a metal matrix composite are also available.

Suppliers provide stainless steel alloys in many stock shapes and forms. Semi-finished stock shapes are suitable for part fabrication by machining, assembly, or other processes. They are also used as feedstock for casting, forging, and spinning. Common stock shapes and forms for stainless steel alloys include bars, rods, tubes, plates, profiles, sheets, strips, shims, spheres, foil, wire, billets, slabs, and blooms. Materials are also supplied as billets, ingots, powders, fillers, and reinforcements. Round, hexagonal, coil, and hollow stock are also available. There are two basic types of anodes. Plating anodes are in used in plating or electroplating processes. Sacrificial anodes are used to protect stainless steel or other metal structures from corrosion.

Selecting stainless steel alloys requires an analysis of dimensions, production processes, and performance features. Outer diameter (OD), inner diameter (ID) overall length, and overall thickness are important dimensions. Most materials are cast, wrought, extruded, forged, cold-finished, hot-rolled, or formed by compacting powdered metals or alloys. Electric arc furnaces are used to produce very clean metals and alloys with fewer inclusions and lower variability. Performance features for stainless steel alloys include resistance to corrosion, heat, wear, and shock. Cold worked metals have good compressive strength and wear resistance under room temperature conditions. Free-machined metals contain lead, selenium, or sulfur additives.

Stainless Steel

The Steel Business Group's Special Steels and Alloys Team has 6 full-time consultants, dedicated solely to the research and analysis of all sectors of the stainless steel and alloys industries.

We have unrivalled expertise in the economics of stainless steel products and markets, our knowledge specifically covering the following areas:

* Producer capacities
* Melted production
* Slab
* Hot-rolled coil
* Cold-rolled coil
* Specific industry issues (such as China, the market for bright annealed stainless, etc)
* Consumption
* Trade
* Prices

The reputation and quality of the Special Steels and Alloys Team has made us the world's authority on stainless steel products and markets. Our approach to market analysis is soundly based upon economic fundamentals, while the unparalleled breadth, depth and inter-relationships of our databases provide solid platforms for our forecasting work. The Special Steels and Alloys Team has extensive experience in forecasting, and issues detailed studies covering short, medium and long-term outlooks.

The ability of our consultants to draw on expertise throughout all parts of the Steel Business Group underlines our core strength - our wholly integrated approach to steel industry research and analysis.

AK Steel produces a complete family of stainless steels. Our Stainless Steel Comparator offers a brief description of all of our stainless steels. For more detailed information on specific stainless steel alloys, please view the product literature provided below each section.
Ferritic
Ferritic, or nonhardenable stainless steels, are classified in the 400 series, usually with 10% to 20% chromium content, and are normally specified due to superior corrosion resistance and resistance to scaling at elevated temperatures. With inherent strength greater than carbon steels, ferritics provide an advantage in many applications where thinner materials and reduced weight are necessary, such as automotive emission control systems. They are nonhardenable by heat treating and are always magnetic. Commercially available AISI grades are Type 409, Aluminized 409, 410S, AK Steel 11 Cr-Cb, 430, 434, 436, 439, Aluminized 439, AK Steel 18 SR, 444 and AK Steel 18 Cr-Cb. Typical applications for ferritic stainless steels include petrochemical, automotive exhaust systems, heat exchangers, furnaces, appliances and food equipment to name a few.
Martensitic
Martensitic, or hardenable stainless steels, are classified in the 400 series, usually with 11.5% chromium up to 18% chromium, with higher levels of carbon than ferritics, and are capable of being heat treated to a wide range of hardness and strength levels. Commercially produced AISI grades of this class are Type 410, 410H, 420, and 420HC. Martensitic stainless steels are used extensively in cutlery, sport knives and multi-purpose tools.
Austenitic
Austenitic, or nonmagnetic stainless steels, are classified in the 200 and 300 series, with 16% to 30% chromium and 2% to 20% nickel for enhanced surface quality, formability and increased corrosion and wear resistance, and are nonhardenable by heat treating. These steels are the most popular grades of stainless produced due to their excellent formability and corrosion resistance. All austenitic steels are nonmagnetic in the annealed condition. (Depending on the composition, mainly the nickel content, austenitics do become slightly magnetic when cold worked.) Austenitic stainless steel grades include: Type 201, Nitronic 30, 301, 304, 305, 309S, 316, 316L, and 321. Austenitics are used for automotive trim, cookware, food and beverage equipment, processing equipment, and a variety of industrial applications.
Precipitation Hardening
Precipitation Hardening stainless steels, or hardenable chromium-nickel alloys, are classified as martensitic or semi-austenitic. They develop their high strength and hardness through a variety of heat treatments. They are used in aircraft parts and commonly viewed as bar alloys, but are also available in flat roll products with a very high strength-to-weight ratio. The martensitic PH steels are used in aerospace, chemical and petrochemical, and food processing applications. Semi-austenitic grades are 17-7 PH and PH 15-7 Mo. They are austenitic in the annealed state, but martensitic in the hardened condition. Other grades of PH alloy stainless steels include 17-4 PH and 15-5 PH. The PH grades achieve high tensile properties in heat treated conditions. Applications for PH alloy steels include aerospace components, flat springs and retaining rings, among others.
Duplex Alloy
Duplex alloy stainless steels contain a mixture of austenite and ferrite in their structure, and exhibit characteristics of both phases with higher strength and ductility. Nitrogen is added to the second generation duplex alloys and provides strength and improved weldability. NITRONIC 19D is an example of a duplex stainless steel grade with good cyclic oxidation, high strength and good stress corrosion cracking resistance. 2205 duplex stainless steel is a grade that offers very good pitting and uniform corrosion resistance, high strength and high resistance to corrosion cracking. Typical applications for duplex alloys are heat exchangers, tubes, pipes, pressure vessels and tanks in the oil and gas and chemical processing industries.