Stainless Steel

Evolution Of Stainless Steel

“ Starting from rust, men have produced something which looks like platinum and resists chemical attack like gold, and yet a square inch can support a quarter of a million pounds. This is the crowning achievement of metallurgy: Stainless Steel-The Miracle Metal! “- Carl Zapffe, metallurgical consultant, 1960

In early 20th century researchers worked around the world in the development of new, stainless and acid resistant steels, especially for the chemical industry. Then already known nickel and chromium steels were for the increasing demands of the chemical industry prone to corrosion and brittleness.

Strauss and Maurer, the fathers of the stainless steel, reduce the carbon content to below one percent. First they combined chromium and nickel as alloying elements, and developed a suitable method for the heat treatment to improve corrosion resistance and strength of the steel. Thus began the worldwide success of stainless steels.

The rapid success of the stainless steel market in the 20s of the last century was the development of an economic process for its production and processing with major challenges. Thus, the first stainless steels were also produced in oil-fired, tilting pans. Only the invention of induction melting furnaces simplified the process. Early 60s was the melting technique in a two stage process – changed – with optional vacuum (VOD) or argon (AOD). The new production technique lowered the cost of production and at the same time extended the range of properties sustainably. In the 80’s were created with the introduction of the continuous casting method, the conditions for a near net shape casting – another quality and commercial milestone. Computer-aided control engineering drove the reproducibility of stainless steel products and much to advance further the growing technological differentiation opened up new application areas.

New production methods for growing demand

The rapid success of the stainless steel market in the 20s of the last century was the development of an economic process for its production and processing with major challenges. Thus, the first stainless steels were also produced in oil-fired, tilting pans. Only the invention of induction melting furnaces simplified the process. Early 60s was the melting technique in a two stage process – changed – with optional vacuum (VOD) or argon (AOD). The new production technique lowered the cost of production and at the same time extended the range of properties sustainably. In the 80’s were created with the introduction of the continuous casting method, the conditions for a near net shape casting – another quality and commercial milestone. Computer-aided control engineering drove the reproducibility of stainless steel products and much to advance further the growing technological differentiation opened up new application areas.

The rapid success of stainless steels can be seen impressively by the production volumes.18,000 kg of anno 1914 the demand surged to 56 tons in the following year. 1950, the worldwide production amount is 1.0 million tons in 1987 already 8.2 million tonnes, 2005 even 24.7 milliontons. 2011 a total of 33.8 were million tonnes of stainless steel produced. The current significance of the material can also be seen on the internet: Only the Google search engine refers to 320,000 posts about the term “stainless steel”. Whether in industry, research, mechanical engineering, architecture and construction, medicine, environment or everyday – excluding stainless steel, the world is no longer conceivable.

Chemical industry as an engine of material development:

Driving force behind the invention of stainless steel was the chemical industry, the overheated gases and vapors studied resistant materials for equipment and components. Parallel to the differentiation of the alloy variants in subsequent years new techniques and products have been developed. Increasingly gained weldability and formability of the new material in importance. Growing system sizes in the chemical industry demanded from plates, welded vessel and longitudinally welded pipes to connect the devices. In quick succession, boilers, columns, heat exchangers, centrifuges, transport and storage tanks, valves or pumps came from stainless steel, acid-and heat-resistant stainless steel on the market. Whether for the production and processing of acids, hydrogenation of coal or tar distillation of liquid mixtures, for textile fiber production, petrochemical, mineral recovery, the solid-liquid separation in wastewater treatment plants or in the food and beverage industry: The application range of chemical resistant and temperature resistant stainless steels is now almost limitless. A significant contribution to safety in making stainless steel tankers with multi-shell tanks for the transport of chemicals, gases, or frozen foods. In oil production for piping are also increasingly ferritic-austenitic duplex steels. These in 1933 discovered stainless steels are much stronger than other stainless steels. They withstand the mechanical stresses caused by waves, currents, and external pressure of up to 3,000 meters water depth, as well as chemical attack inside the pipe by the pumped oil or natural gas and salt water on the outside wall of the tubes. Their higher basic strength also allows thinner walls compared to conventional austenitic stainless steels. End of the 80s was developed with Lean Duplex an alternative to the established duplex steel and austenitic stainless steels. Thanks to its lower nickel content of the material won 1.4362 early 21st Century the face of volatile nickel prices in importance. Compared with conventional heat exchangers made of stainless steel plate heat exchanger tubes can from lean duplex sheets – with the same performance – reduce size, weight and costs. Except in chemical environments lean duplex is processed in the construction industry increasingly.

Timeless aesthetics, sustainable technology in construction

Only a few years after its invention, stainless steel as a building material has inspired the imagination of architects and planners. The tallest buildings in each of the past 100 years were given by their stainless steel distinctive touch: It all started in 1929, the Chrysler Building in New York, its hood still adorn 4500 large-sized stainless steel shingles. The Petronas Towers in Kuala Lumpur, the Atomium in Brussels, the Burj Khalifa in Dubai or the new landmark of New York, the One World Trade Center, underline with stainless steel their undying importance. In 1976, the heavily corroded metal skeleton of the American Statue of Liberty has been replaced with stainless steel. In the Bibliothèque Nationale de France in Paris 1992, the success story of its stainless steel mesh top. Today the material in architecture is omnipresent. Its fascinating looks and unparalleled functionality inspired to produce new applications both indoors and outdoors.

Stainless, maintain and service, weather resistant and in the highest degree – also in combination with other materials – durable, stainless steel makes itself through long life and minimum maintenance costs paid term. Whether as structural, corrosion-resistant concrete and masonry reinforcement, protective façade, conventional roof cover, green roof, lightning protection, ceiling or floor, in swimming pools, for renovation, for elevators, escalators, doors or gates, balustrades or as a multifunctional, increasingly even medialized Cases car parks, hotels, stadiums, train stations or airports cover Stainless steels from the full range of architecture. The used products are as diverse as the applications and versions. Plates, grilles, panels, fabrics, braids, hollow profiles, rods, wires, screws, clips or point holder, natural, matt, embossed, brushed, colored, with innovative surface coatings against graffiti, fingerprints, with lotus effect or with integrated LEDs – stainless steel makes it possible. In architecture, stainless steel is a synonym for creative expression and sustainability. Competing with composite materials, stainless steels especially score also by their complete recyclability without loss of quality. In the current debate on climate and energy savings are the ecological balance of the material, its increased use an extra boost.

Robust all-rounder for automotive and railway construction

Recognized early and the car industry the potential of stainless steel. 1936 Ford produced in Detroit prototype of six stainless steel bodies. Since the 50s exhaust parts are made of stainless steel. In the late 60s, Porsche’s legendary 911 in a variant of stainless steel, which can be seen today in the German Museum in Munich. Latest high quality exhaust systems are constructed entirely of stainless steel. In systems for fuel injection, particulate filtration or gas treatment of high-performance material has long been indispensable: the prevailing extreme conditions – temperatures up to 700 ° C, pressures up to 3 bar, aggressive media and mechanical vibrations – he holds any other building material permanently Stand A holistic view of material production, component manufacturing, life and makes recycling stainless steel in vehicle into a tireless driver of new developments. Due to its high elongation values and strengths, he is being used increasingly as reinforcement for A-and B-pillars, roll bar, protection and frame components. The thin and so lightweight components reduce material costs, vehicle weight and fuel consumption With this efficient property profile Stainless steel is also the world of rail vehicles on the train.1934 Edward G. Budd, Philadelphia, the famous, only 104-ton Burlington Zephyr built with diesel locomotive and three carriages.

For the body of innovative train, he used 23 tons of cold-rolled stainless steel. In order for this, designed for 72 passengers train was a real lightweight and twice as fast as conventional trains were powered by steam locomotives. He was the icon of technology, now part of the permanent exhibition at the Museum of Science and Industry in Chicago. In the 50s, from high-alloy steel turbine blades set in the first driven by gas turbine engines set new standards. For rail vehicles of the latest generation of innovative lightweight construction concept is more relevant than ever: strength at low thickness, crash and fire resistance of stainless steel make today become the leading material for all kinds of sophisticated but also economic body structures. For the high-quality look of the stainless steel can often be dispensed with exterior painting, which also accounts for the usual regular repainting. -Passed a surface protects the car in front of graffiti and makes them less sensitive to overall vandalism.

Sterility of Medicine, beverage and food industries

Shortly after the discovery of stainless steels the early ’20s has been increasingly recognized its importance for medical equipment, tools and facilities. The decisive factor here was its resistance to high temperatures and aggressive chemicals, even common withstand sterilization and disinfection problems. Despite mechanical, thermal and chemical stress, the duration of smooth, hard material surface is not rough or cracked, so that even with intensive use any bacteria and fungi colonize. In 1926, the first implants of stainless steel were developed. Even today, artificial knee joints of stainless steel meet the current state of research.

The strict hygiene regulations for surgical instruments and surgical equipment apply analogously in the food and beverage industry. Here also ensures the specific surface properties of the material, a smooth, aseptic cleaning and reliably prevented that a nutrient medium for microorganisms is formed. In the dairy and meat industry makes these good ductility and seamless manufacturing the material for hygienic engineering and economic production processes. Kitchens, dairies, breweries, wineries and juice manufacturers use for decades in stainless steel. His extraordinary chemical and thermal stability – even under extreme temperature fluctuations, such as those required for the sterilization of milk or pasteurized fruit juices – thanks to the extensive use of stainless steel for manufacturing, storage and transport of acidic products. Since it is completely inert and therefore tasteless addition, it does not affect taste or appearance of the produce.

Material for new lifestyle

The amazing range of properties and the eye-catching presence in architecture and technology paved stainless steels early on the way to the household: in 1921, the first stainless steel cutlery, more and more everyday objects appeared followed. In the 50’s were designed by the pioneer of industrial design, Wilhelm Wagenfeld, a variety of legendary commodities made from stainless steel. The organic shape of its industrially produced cutlery, bowls, egg cups, salt and pepper shakers, butter dishes and vases brought him as the modern-sounding material worldwide recognition. Formative influence also had the puristic designs Scandinavian designers that are of the unpretentious character of stainless steels congenial. 1956 revolutionized the first stainless steel razor blades from Wilkinson Sword, the beard trimming. In 1958, the triumph of the machine began with drums made of stainless steel. At the same time sinks were from the easy-care, durable materials bare the quintessence of modern kitchen equipment. Unstoppable stainless steel conquered with quality seal from now on its leading role as a material for cookware, kitchen appliances, fittings, sanitary ware, radiators, appliances and accessories for the kitchen and bathroom. His timeless aesthetics, durability and easy care functionality make it the classics of modern life.

High performance for high-tech industries

In the energy industry, clean room technology, environmental technology and telecommunications and electronics, the resistance of stainless steel against corrosion various stresses regularly sets new standards. Whether the power plant or Windradbau, in heat exchangers or flue gas filters for solar panels or biogas plants -: The high-tech material is exactly adjusted by individual alloys on the increasing demands In telecommunications, paper-thin stainless steel foils and precision strips are used, which are coated with nickel and gold in the nanometer range. Up to 10 million circuits must make it stamped snap discs reliably.

Fountain of youth for ideas of tomorrow

For 100 years, stainless steel provides for an almost unlimited range intelligent value. Multifunctional, low maintenance and highly durable, it opens up new applications constantly. Timeless contemporary he wears increasing demands worldwide engineering bill. Rising expectations for environmental performance, value retention and profitability make stainless steel with seal of quality in ever new forms of universally sought after solution and help him to eternal youth.

What Makes Stainless Steel Special

What is Stainless Steel?

Stainless steel is a generic term for a family of corrosion resistant alloy steels containing 10.5% or more chromium.

All stainless steels have a high resistance to corrosion. This resistance to attack is due to the naturally occurring chromium-rich oxide film formed on the surface of the steel. Although extremely thin, this invisible, inert film is tightly adherent to the metal and extremely protective in a wide range of corrosive media. The film is rapidly self repairing in the presence of oxygen, and damage by abrasion, cutting or machining is quickly repaired.

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Green Metal

Metals are extracted from their natural and most stable states as ores after a lot of work. This work consumes a great amount of energy and effort. All these efforts affect our environment adversely in one way or another. Therefore, the more we recycle the scrap / end-of-life metals, the better off we will be as only a fifth of effort is required in recycling. Did you know, 90% of stainless steel is recycled?

Recycling of Stainless Steel Scrap

Today, environmental factors are at the forefront of material selection for specifiers. Stainless steel’s long service life, 100 percent recyclability and its valuable raw materials make it an excellent environmental performer.

Stainless steel objects rarely become waste at the end of their useful life. Recycled stainless objects are systematically separated and recovered to go back into the production process through recycling.

As well as iron, stainless steel contains valuable raw materials like chromium and nickel which makes recycling stainless steel economically viable.

Stainless steel is actively recycled on a large scale around the world by recyclers who collect and process scrap (recycled stainless steel) for re-melting all around the world.

Scrap collection

The use of stainless steel scrap is fundamental to the steelmaking process. There are two types of scrap – reclaimed scrap (old scrap) and industrial scrap (new scrap). Reclaimed scrap includes industrial equipment, tanks, washing machines and refrigerators that have reached the end of their service life.

Industrial scrap includes industrial returns or production offcuts from manufacturing by industrial engineering and fabrication sources.

Today, stainless steel is made up of approximately 60% recycled content including:

  • 25% reclaimed scrap
  • 35% industrial scrap
  • 40% new raw materials

The useful service life of stainless steel products is long so the availability of scrap is dependent on levels of production from decades ago.

With an average content of 25% of old scrap, stainless steel is close to the theoretical maximum content of material from end-of-life products.

Recycling the scrap

Specialised expertise and sophisticated technology is needed in recycling to separate and prepare each type of alloy for remelting.
A recycling processor feeds the scrap into a large shredder to break it into smaller pieces.
It is then chemically analysed and stored by type.
This process may include ‘blending’ the scrap into chrome steels, nickel alloys and other types of stainless steels.
After blending into piles for specific customer requirements the scrap is then loaded into containers for export to overseas mills.

The global market for scrap

Virtually, all Australian stainless steel scrap goes overseas. There’s a small market for stainless steel scrap in Australia for use in the foundries business. Foundries often use profile offcut or plate material scrap products.
At least 30,000 tonnes of stainless steel scrap in Australia will be exported a year to stainless steel mills in countries including China, South Korea, Taiwan, India and Japan.
China, for example, is using approximately 800,000 tonnes of industrial scrap. Reclaimed scrap is also on the increase in China and is expected to reach 2.5 million tonnes in 2005.

For mills, scrap is important because recycled stainless steel contains valuable raw elements including chromium, nickel and molybdenum that are gathered, processed and reused in the production process. The more scrap used in furnaces by mills, the less raw materials are required in the production process.

Stainless steel mills

Scrap along with other raw materials, ferrochromium (chrome/iron), ferro moly (molybdenum/iron) and nickel are blended into an electric furnace.

After melting, impurities are removed, the molten metal is refined and the chemistry analysed to determine what final adjustments are necessary for the specific type of stainless steel being produced.

The molten stainless steel is then cast into slabs or billets before production of plate, sheet, coil, wire and other forms in preparation for use by industrial manufacturers.

The stainless returns to you

Industrial manufacturers produce stainless steel items that you use everyday including cutlery, pots and pans, kitchen sinks and many architectural, industrial and other components.

At each stage of the production and use process, stainless steel retains its basic properties and utility value. Unlike many industrial and engineering materials, stainless steel may be returned to its original quality in the supply chain without any degradation.

You can be assured that even after its long service life, your environmentally-efficient stainless steel will always return to you bright, shining and new!

ASSDA acknowledges the assistance and contribution of Ignatius Brun of ELG Recycling Processors, the International Stainless Steel Forum (ISSF), the Nickel Institute and Peter Moore of Atlas Specialty Metals in the production of this article.

For more information about stainless steel, contact the Australian Stainless Steel Development Association on 07 3220 0722 or visit www.assda.asn.au

Consumption of stainless steel scrap – 2004
  • China — 2.8 million tonnes of production using 900,000 tonnes of scrap.
  • Japan — 2.4 million tonnes of production capacity using 900,000 tonnes of scrap.
  • South Korea — 2.3 million tonnes of production using 800,000 tonnes of scrap.
    Product mix 80% austenitic, 20% ferritic.
  • Taiwan — 2.6 million tonnes of production using 600,000 tonnes of scrap.
  • India — 1.4 million tonnes of production using 300,000 tonnes of scrap.

Note: Australia sends a proportion of stainless steel scrap to all of the above countries.

Life Cycle Costing

Cost is a simple yet complex concept. It has many dimensions and implications attached to it. Speaking strictly in economic terms, cost is always associated with Value of Money. The cheapest alternative may not always be the best option to choose when entire life of the product is taken into account. Therefore, Life cycle costing becomes an important key.

Life Cycle Cost (LCC) analysis is a means of quantifying the choice of materials for a product or construction, with the aim of selection of the most economic alternative. Stainless steel normally comes with a initial higher cost of material, but its longer life due to excellent wear & corrosion resistance features, low requirement of maintenance and recyclability compensate for the higher initial costs and makes it a environment friendly material or ‘Green Material’.

How LCC is calculated?

LCC enables potential long-term benefits to be assessed against short-term expediency. Materials costs are assessed with their implications, for example initial outlay, maintenance and its frequency, downtime effects, production losses, repair, replacement, and other operationally related costs such as manpower and energy consumption

LCC = Acquisition Cost + Fabrication and Installation Cost + Maintenance Costs (periodic) + Replacement Costs (periodic) + Cost of Lost Production (periodic) – Residual (Scrap) Value.

Why LCC is important?

With advent of new technologies in every stream of engineering and the fast pace of the infrastructural and industrial progress in India, the engineers are faced with more and more daunting challenges in designing and constructing robust structures and machineries that are long lasting and low in maintenance. It is necessary that engineers think in terms of the total life cycle costing of their designed structures and not the initial capital cost.

Major culprit of the loss of value and reduction is useful life of any structure is either wear or corrosion in one way or the other. Corrosion causes plant shut downs, waste of valuable resources, loss or contamination of products, reduction in efficiency and costly maintenance. Awareness with respect to corrosion is very less in our country. People must develop a mindset and attitude to fight corrosion, says a player from the industry. Did you know that every year corrosion causes the USA lose 0.6 Trillion USD (about 4% of their total GDP) due to corrosion? If you think about that money, it is 33% of India’s total GDP (1.85 Trillion USD). In India, we lose about Rs. 1, 00,000 Cr to corrosion every year.

Stainless steel by virtue of its special chemical composition is one such value added material of construction that offers long lasting and low maintenance structures. A good understanding of Life cycle costing (LCC) is important to make informed choices and create values that will serve for years to come.

Making Of Stainless World

Innovative Use Of Stainless Steel International Projects
Innovative Use Of Stainless Steel Domestic Projects

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