Evolution of Stainless Steel

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PAST PRESENT AND

FUTURE OF STAINLESS

STEEL

Erdal YAVUZ-Huseyin ZENGIN-Mustafa SEYREK

UNIVERSITY OF SHEFFIELD

MARCH-2013


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1. INTRODUCTIONStainless steel is the common name for various types of steels which contain 10.5% or more

chromium by weight. The addition of chromium makes steel stainless. It has therefore been

widely used in many different industries because of its unique features such as resistance to

corrosion, fire and heat, as well as hygiene and strength. (BP, 2013)

Scientists discovered stainless steel in the the 19 th century, but there has been a much dispute

regarding who actually discovered this alloy. It is generally accepted that Harry Brearley

discovered stainless steel in 1913 in Sheffield England while he was working on a project to

prolong the life of rifle barrels from erosion during use(The New York Times, 1915).During

this project, Brearley made a certain number of alloys which contained different rate of

carbon from 6% to 15%. Through his experimentation, Brearley produced a steel with 12.8

chromium and 0.24% carbon on the 13th August 1913(BSSA, 2013).

At this time, he needed to etch his samples with nitric acid in order to examine them under a

microscope. Based on nitric acid, Harry Brearley found that these steels extremely resisted

chemical attacks. He then exposed his specimen to vinegar, lemon juice and other food acids

but he found same results. Afterwards, he recognized how these steels could contribute tocutlery industry. He subsequently manufactured knives and initially decided to call his

invention RustlessSteel but it was Ernest Stuart, the manager of Mosleys cutlery, who first

used term Stainless Steel after some experiment with vinegar (VW, 2013). Accordingly,

martensitic chromium stainless steel was, to an extent, accidently discovered by Harry

Brearley while he was seeking corroding-resistant alloy for gun barrels (BSSA, 2013).

Between 1912 and 1914 employees of the Krupp Iron Works in Germany developed

austenitic stainless steel by using 15-40% chromium,


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2. AN OVERVIEW OF DEVELOPMENTS IN STAINLESS STEELS INTERMSOF TYPES, MARKETING AND PRODUCTION

2.1.Types and Marketing

After stainless steel was discovered and commercialized, the awareness of its superior and

unique properties created an appealing research area and a growing demand for an immense

number of applications. Several types of stainless steels have been developed based on their

microstructure so far. Those types of steels are used numerous applications: hand tools,

reinforcing bars, roofing, claddings, automobile parts (exhaust, engine, fasteners etc.), marine

constructions, catering equipment, kitchen appliances, water pipes, pressure vessels, chemical

and surgical equipment and transportation (cars, trucks, trains etc.), to name but a few. The

number of stainless steels applications and the usage rate of stainless steels have always

increased due to the development of new types of stainless steels that offer lower product

costs and better or comparable corrosion resistance and mechanical properties. The line graph

below Fig.1 presents the growth rate of crude stainless steel production in the world for the

last around 50 years. As it can be seen, the annual growth showed a gradual increase until the

mid-1970s and then rose steeply until 2011 except the slight falls because of the crises.

Undoubtedly, that rate will continue to go up in the future due to the developments in moreadvantageous new types of stainless steel alloys in terms of cost and material properties.

Figure1. Annual growth rate of world stainless crude steel production (19502011)


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International Stainless Steel Forum

As it is stated before, stainless steels attain their stainlessness by chromium addition at least

10.5 wt%. This composition of chromium forms a self-repairing chromium oxide on steel

surface that protects steel from corrosion. The addition of some other particular alloying

elements can enhance the properties of stainless steels. The major alloying elements apart

from chromium are nickel, molybdenum, nitrogen and manganese. Nickel is added in high

compositions, over 8%, primarily to increase the corrosion resistance, toughness and strength

of stainless steels and to form heat-resisting steels with stabilizing austenite phase.

Molybdenum enhances the pitting and crevice corrosion resistance of stainless steels. Despite

these good properties, nickel and molybdenum are expensive elements. Because of that, in

recent years, developers have been more focused on reducing the composition of these

elements with trying to obtain the same or comparable properties as high nickel and

molybdenum added stainless steels. For instance, nitrogen and manganese are austenite

stabilizers like nickel and they provide good corrosion resistance, strength and toughness as

well so that their presence can be an alternative to nickel.

Stainless steel can have mainly three different microstructures and the types of stainless steel

are based on these microstructural properties. These are ferritic, austenitic and martensitic.

They are achieved by changing the chemical compositions of elements in stainless steels.

Apart from the main microstructure, stainless steels are divided into several classes that are

ferritic stainless steels, austenitic stainless steels, martensitic stainless steels, duplex stainless

steels and precipitation hardening stainless steels. Austenitic stainless steel is the most

common type of stainless steels and is used for various applications. It has a FCC crystal

structure and has its austenitic structure is because of the high concentration of nickel in it.

Austenitic stainless steels are non-magnetic, weldable and excellent corrosion resistant

materials and have good mechanical properties. Ferritic stainless steels are iron-chromium

alloys and have BCC crystal structure. Although these stainless steels are ductile and

formable, their high-temperature strengths are not as good as austenitic steels. Alloying with

carbon and nitrogen can increase corrosion resistance to chloride. Ferritic stainless steels can

be utilized in some kitchen appliances and are the most affordable stainless steels. Martensitic

stainless steels have a composition balance of carbon and nickel versus chromium and

molybdenum. The carbon content of these stainless steels influences the formability and

weldability properties. Duplex stainless steels have almost the same amounts of ferrite and

austenite structure. These types of steels include around 21-25 % chromium and 5% nickel


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with a small amount of nitrogen and molybdenum. In recent years, duplex stainless steels

have become very popular and preferable type of stainless steels due to their competitive

properties. These steels may have greater strength and corrosion resistance and lower cost

than any other types of stainless steels. Besides, leaner duplex steels can offer much less cost

and comparable properties due to the low compositions of expensive alloying elements such

as nickel and molybdenum. Precipitation hardening stainless steel contain chromium and

nickel but have different alloying elements that

can form precipitates to increase the strength. The alloying elements can be aluminum,

copper or titanium.

Figure 2. Stainless Steels Family Chart

2.2.Production of Stainless Steels

With particular restrictions in some types, stainless steels could be fabricated and shaped in

traditional ways. The manufacturing processes are casting, wrought form production and

powder metallurgy (P/M). A wrought stainless steel product can form as wire, strip, plate,

sheet, pipe, bar, tubing and semi-finished products such as blooms, slabs, and billets. Most ofthe stainless steel products are plate, sheet and strip (cold-rolled flat products). Figure 3


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demonstrates the most common mill processes for producing numerous wrought products of

stainless steel. The production process of stainless steels consists of two main steps (ASM,

2000).

Figure 3. Manufacturing process of stainless steels

First stage is the ferroalloys and scrap melting process in electric arc furnace (EAF) and the

second stage is the refinement process by argon oxygen decarburization (AOD) illustrated in

Figure 4. AOD adjusts the carbon composition and removes impurities. It is the most

economical method for stainless steel production with minimizing the loss of precious

elements (ASM, 2000).

Figure 4. Argon Oxygen Decarburization (AOD) Process


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The main advantage of the combination of EAF and AOD is the size. EAF can supply 45000

pounds of powder, which is a much larger amount of powder than that of induction furnace

(1000-4000 pounds). Therefore, some properties such as flow, density, sintered and green

properties are kept constant by production in one batch with such that large capacity. Another

advantage of the EAF/AOD process is decarburization. The oxidation of carbon in AOD is

more preferential than that of chromium. Hence, the wider range of materials can be used

such as green scrap and high carbon ferro-chromium. Decarburization is obtained in liquid

steel by the oxidation of carbon so that carbon monoxide is released from the melt (Ian,

2002).

Alternatively, for melting process; electron beam melting, vacuum induction melting, electro-

slag remelting and vacuum arc remelting can be used. However, electric arc furnace (EAF)

and argon oxygen decarburization (AOD) are the most commonly employed melting and

refining processes for stainless steel production. For the mill forms of sheet, plate, bar and

strip, the final stage consist of annealing, hot reduction, cold rolling and cleaning whereas

there are further processes for the forms such as tube and wire to give the stainless steel

product required size (Ian, 2002).

3. Applications of Stainless Steel3.1. Stainless Steel in Buildings and Civil Engineering

Stainless steels have not been considered as indispensable structural materials for all civil

engineering applications. There have always been some imperative needs in where the

stainless steels have been used such as bridges, roofs, dams, parking garages, tunnels, sea

walls, claddings and so on. The major requirements that make stainless steels more desirable

for those applications than other conventional structural steels are primarily high corrosion

and staining resistance, low maintenance, longevity and aesthetic purposes. Furthermore,

stainless steels could meet all expectations as structural materials in terms of mechanical

properties. However, the use of stainless steel in structural applications has remained low

because of its high cost. Today, developments in new types of stainless steel are providing

with an opening for the future of stainless steel with bringing down the cost of stainless steels

in civil engineering applications.

Stainless steel refers to a broad range of types and alloys. For civil engineering applications,

there are two main alloys: the austenitic and duplex stainless steels. Both these types contain


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iron, chromium, nickel and molybdenum. As it is well known, the corrosion resistance of

stainless steels is highly dependent on the composition of chromium and it can be increased

by nitrogen and molybdenum. Nickel ensures the fine microstructure and good mechanical

properties of the steel (Lo&Shek&Lai, 2009).

In civil engineering applications, selecting an appropriate grade of stainless steel is based

highly on the factors that are related to corrosion risk of environment and properties of

stainless steel. These factors may include exposure to chloride, micro and macro

environmental effects, surface roughness and ability of corrosion resistance at joints

(fabrications effect) (Gedge, 2008).

Austenitic stainless steels have always been the most prevalent type of stainless steels in civil

engineering applications by engineers. High composition of nickel in austenitic stainless

steels stabilizes austenitic structure, enhances ductility and workability. Moreover, hot-rolled

austenitic steels have excellent toughness and weldability. However, the mill cost of stainless

steels is highly dependent on nickel (rare element) content because the influence of the prices

of nickel is the most important factor on keeping out stainless steel with high nickel and

molybdenum compositions from all civil engineering applications. As it can be seen from

table 1 and table 2, austenitic stainless steels have larger compositions of nickel than that in

duplex stainless steels. Therefore, it can be deduced that austenitic stainless steels are the

most affected by the nickel price which has experienced a significant fluctuation because of

stock market factors (Gedge, 2008).

Table 1. Composition of three alloys of austenitic stainless steel.

For many civil engineering applications, duplex stainless steels have become an appealing

alternative to austenitic stainless steels in recent years on account of their excellent strength


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and low expense for raw materials or alloying elements. Both the significance of conservation

of the rare elements (primarily nickel and molybdenum) and the need for reducing the cost of

final product bring about new developments effectively in duplex stainless steels with low

nickel and molybdenum content. These types are called lean duplex stainless steels. The

compositions of two types of lean duplex steels (1.4162 and 1.432) are shown in Table 2. As

it can be seen from the table, lean duplex steels have much less nickel and molybdenum

composition than established duplex and austenitic steels. Lean duplex stainless steels can

also be as high strength as traditional duplex steels and as high corrosion resistance as

established austenitic stainless steels with affording low cost. Therefore, it can be predicted

that these steels will be chosen over other types of stainless steels for construction purposes

(Baddoo&Burgan, 2001; Gedge, 2008; Lo&Shek&Lai, 2009).

Table 2: Composition of four alloys of duplex stainless steel.

A corrosion resistance comparison between duplex and austenitic steels is shown below in

Figure 1. 1.4462 type steels are the most suitable for all circumstances but not as economical

as 1.4301 and LDX2101. Unless there is an extreme corrosive environment, LDX2101,

which is a type of lean duplex stainless steel, would be the best choice considering its low

cost.


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Figure 5. Comparison of corrosion resistance of duplex and austenitic stainless steels

It is likely that the tendency to increasing usage of duplex and lean duplex stainless steels as

structural materials will carry on in the future with regard to low material cost, high strength

and comparable corrosion resistance. The awareness of the advantages of duplex stainless

steels has encouraged researchers to develop competitive alloys of stainless steel for civil

engineering applications. Taking into account of production cost of steel making and variable

prices of alloying elements designated by The Alloy Adjustment Factor (AAF), lean duplex

stainless steels step forward as structural materials due to low compositions of expensive

alloying elements combining with comparable mechanical properties and corrosion resistance

and these are projected to be widely used in civil engineering applications. In addition to the

improvements in lowering fabrication cost of stainless steels, avoiding from the potential

expensive and disrupting maintenance and the need for sustainable structures are significant

for civil engineering applications. As long as leaner stainless steels meet these requirements,

they can be expected to be the most preferred structural materials in all civil engineering

applications in the near future.

3.2 Stainless Steel in Food and Beverage Industry

The invention of stainless steel at the beginning of the 20 th century was very important

milestone for the food and beverage industries. Stainless steel has been chosen in the food

industry because it is resistant to corrosion, inert and it surfaces can be easily cleaned. It can

also be produced with several techniques, relatively easy to recycle and can exhibit an eye

catching appearance (Newson, 2003). Stainless steels have, therefore, been substantially used

in kitchen equipment for the preparation, storage, and food displays (SSAS, 2000).

As the material can be easily cleaned it has played important role in improving kitchen

equipment hygiene. Stainless steels cleanability is similar to that of glass and porcelains,

but superior to plastics (Mohan, 2012). Moreover, stainless steel in contact with food or

beverage, than this situation may affect colour and taste. The property of stainless steels

surface finish can not only provide cleanability and corrosion resistance, but also preserve

food colour or smell (SSAS, 2000).


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Table 3. Typical Applications of Stainless Steels used in Food Preparation. (SSAS, 2000)

Most foodstuff and drinking water contact material in stainless steels are widely produced

from austenitic stainless steel because of its perfect corrosion resistance, fabrication feature

and great deal of mechanical properties. Martensitic stainless steel is vastly used for cutlery

and grinding equipment. Besides, high-quality knives are manufactured by martensitic

stainless steel which contain high carbon, vanadium and molybdenum (T. Newson, 2003).

Furthermore, ferritic and duplex stainless steels have also used in food and beverage industry.

Table 1 illustrate the applications of stainless steel which is used in food industry.

Currently, approximately 38% of all stainless steel have been manufactured for food and

beverage industry and also it has begun to use in new area such as sugar industry. Sugar is

highly corrosive on various kinds of metals. Ferritic stainless steel, however, can be used to


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use in sugar industry machinery in order to enhance performance. Nevertheless, even though

CS444 stainless steel is not normally used in drinks industry, it is used du its suitability for

this application. Moreover, ferritic stainless steel has thus replaced 304 austenitic stainless

steel for industrial kitchen hob applications (ASSDA, 2006).

The consumption of duplex stainless steel has substantially increased as a result of greater

food and beverage applications. It is also a suitable steel for storage tank application because

of its high strength and cost reduction. Moreover, its corrosion resistance is better than

austenitic stainless steel: this property therefore makes it attractive to manufacturers

(OUTOKUMPU, 2010).

3.3. Stainless Steel in Medical DevicesStainless steels are used for medical purposes approximately for 90 years. It means that

medical devices are one of the main application fields of stainless steels. As looked at

historical background, chronology could be shown briefly as follow;

- In 1926, E. W. Groves used screws which are made of 18-8 Cr-Ni austenitic stainlesssteel for fixing of femoral neck fractures.

-In 1936, Intermedullary nail produced stainless steel was used for comminuted ulnafracture by Rush.

- In 1947, American College of Surgeons decided that 19Cr-9Ni and 18Cr-8NiStainless steel alloys were suitable for implantation.

- In 1958, The use of stainless steel for hip components, Charnley practised with thetotal hip replacement

- In 1960s, To correct spinal curvature, Rods known Harrrington rods were developed.- In 2000s, Nickel Free stainless steels are being researched (Heubner&Wedohl,2009).

Today, A wide range of medical applications where they come into contact with human tissue

and skin are made from stainless steels. This situation could be explained that stainless steels

are expected to perform without any negative effetcs on health system

(Santonen&Stockman&Zitting, 2010).

Within Medical devices, Implants are more concerned materials so they are generaly made

of austenitic type of stainless steel. The essential reasons are that austenitic stainless steels


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have excellent ductility, toughness, formability, ductility and also they are non-magnetic

(Bombac&Brojan&Krkovic, 2007).

Figure 6. A Picture of Knee and Hip Implant

However, typical austenitic stainless steels contain 8-10 % Ni. So the presence of high

quantity of nickel , these materials have toxic and allergic effects on human body. The Ni

ions could cause cutaneous iflammations which has negative reactions such as eczema,

reddening, and itching for the itching. Therefore Nickel is the critical element in austenitic

stainless steels which can impart FCC crystal lattice due to Nickel content. It means Nickel

is the most effective austenite stabilizer element. Moreover, Nickel has price speculation in

Metal World beacuse of high cost and low availability (Bombac&Brojan&Krkovic, 2007).

As taken account of all these issues, If Nickel-Free stainless steel is being expected to be

common, it means that we need another austenite stabiliser alloying element. Recent

researches focus on Nitrogen which would be used austenite austenite forming element . In

addition, Researches showed that nitrogen makes austenitic stainless steel stronger and more

wear and fatigue resistant. Moreover Nitrogen can be found everywhere easily. (i.e. no more

speculations on cost). Therefore It is expected that nitrogen containig austenitic stainless

steels ( known 200 series stainless steel ) would be more considerably used in the future

(Bombac&Brojan&Krkovic, 2007).

As mentioned earlier, Austenitic stainless steels are non-magnetic materials. Implants are

checked out regularly and this could only be possible using MRI method. Because

widespread use of magnetic resonans imaging , Implants must not be affected by strongmagnetic field (Bombac&Brojan&Krkovic, 2007).


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Now another important application field which concerns Medical is Surgical devices. Easy

cleaning and sterilisation of these instruments are so important. These are known as Non-

implant medical devices. Generally , Martensitic and austenitic stainless steels are used for

making these tools such as clips, scissors, forceps but mostly martensitic stainless steels to

keep sharp tools and harder than austenitic stainless steel. However, Martensitic stainless

steels could be corrode and stain more likely than others because of higher carbon content

and It is known that blood is a highly corrosive and surgical instruments are generally

subjected to blood (Bombac&Brojan&Krkovic, 2007).

Figure 7. Some Surgical Instruments

4. CONCLUSION

Stainless steels are known Iron-Chromium-Nickel alloys and alloying elements are added to

enhance their microstructure and make main requirements possible. Stainless steels have

unique values that make hem useful for materials engineer and designers. Generally,stainless steels provide good corrosion resistance and a wide range of mechanical and

physical properties for intended applications. They have played inestimable role to the well

being of humankind. However , Their duty are set to carry on to the future by providing

current and future needs.

If we look at the production rate of world crude stainless steels annualy at Fig 1 , we would

see that the amount of demanding stainless steel would not decrease in the future.

Conversely, stainless steels are getting popular in the world.


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Among stainless steel types austenitic stainless steels cover a great majority of stainless

steel market with. However, Duplex stainless steels are being search to replace other grades

with some effective properties, even though they cover just 1 percent of total stainless steel

market.

Today , Recyclability is the key for environmental issues.Corrosion resistance of stainless

steels provide 100 per cent recyclability. This has positive effects on recovery on scraps.

These scraps can be charged into directly melting furnace. So All these make stainless steels

sustainable materials.

Material selection and design criteria cause new seekings and New grades stainless steel

series could appear largely. These are mainly results of economical and environmental issues

and also meeting needs of desirable applications. For example, Arcelor Mittal has designed a

new grade, K44X, stainless steel to meet demanding higher temperature resistance in

automotive industry because of smaller engines being used.

All new developments are to meet higher corrosion resistance, mechanical strength, fatigue

and wear resistance. However, Nickel Free stainless steels are being researched due to the

fact that Nickel prices are getting higher because of low availability and also nickel has

negative effetcs on human body and tissue. It seems nitrogen would take place of nickel in

foreseeable future.

Finally, Stainless steels establish a quite wide market presence from domestic to medical, and

also from food and drink to transportation because of their good properties.


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References:

ASM, 2000, Introduction to Stainless Steel, Available:

http://www.asminternational.org/content/ASM/StoreFiles/06940G_Chapter_1.pdf(Accessed:

2013, March 5)

ASSDA, 2006, September, Industrial Meat Processing Machinery, Available:

http://www.worldstainless.org/Files/issf/non-image-

files/PDF/FoodandBeverageIndustry_2009.pdf(Accessed:2013, March 12)

Baddoo, N., Burgan, B., 2001, Structural design of stainless steel, SCI P291, SCI 2001.

Bombac,D., Brojan,M., Krkovic,M., 2007, Characterization of titanium and stainless steel

medical implant surfaces, Materials andGeoemvironment, 54(2), p.151-164

BSSA, 2001, March 12, SSAS Information Sheet No.3.21, Available:

http://www.bssa.org.uk/cms/File/SSAS3.21-

Stainless%20Steels%20for%20Food%20Processing%20Industries.pdf(Accessed:2013,March 5)

BSSA, 2007, The Discovery of Stainless Steel, Available:

http://www.bssa.org.uk/about_stainless_steel.php?id=31 (Accessed:2013, March 7)

BP, 2013, All About Stainless Steel, Available:

http://www.berkeleypoint.com/learning/stainless.html (Accessed:2013, March 11)

Heubner, U.,Werdohl, D., 2009, Stainless Steel-When Health Comes First, Environment and

Human Health Series 2, P.1-40

Gedge, G., 2008, Structural uses of stainless steelbuildings and civil engineering, Journal

of Constructional Steel Research, 64 (3), p1194-1198.
http://www.asminternational.org/content/ASM/StoreFiles/06940G_Chapter_1.pdfhttp://www.worldstainless.org/Files/issf/non-image-files/PDF/FoodandBeverageIndustry_2009.pdfhttp://www.worldstainless.org/Files/issf/non-image-files/PDF/FoodandBeverageIndustry_2009.pdfhttp://www.bssa.org.uk/cms/File/SSAS3.21-Stainless%20Steels%20for%20Food%20Processing%20Industries.pdfhttp://www.bssa.org.uk/cms/File/SSAS3.21-Stainless%20Steels%20for%20Food%20Processing%20Industries.pdfhttp://www.bssa.org.uk/about_stainless_steel.php?id=31http://www.berkeleypoint.com/learning/stainless.htmlhttp://www.berkeleypoint.com/learning/stainless.htmlhttp://www.bssa.org.uk/about_stainless_steel.php?id=31http://www.bssa.org.uk/cms/File/SSAS3.21-Stainless%20Steels%20for%20Food%20Processing%20Industries.pdfhttp://www.bssa.org.uk/cms/File/SSAS3.21-Stainless%20Steels%20for%20Food%20Processing%20Industries.pdfhttp://www.worldstainless.org/Files/issf/non-image-files/PDF/FoodandBeverageIndustry_2009.pdfhttp://www.worldstainless.org/Files/issf/non-image-files/PDF/FoodandBeverageIndustry_2009.pdfhttp://www.asminternational.org/content/ASM/StoreFiles/06940G_Chapter_1.pdf


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Lo,K.H., Shek,C.H., Lai,J.K.L., 2009, Recent developments in stainless steels, Materials

Science and Engineering, 65 (3), p39-104

Ian, A.W., 2002, Stainless Steel PowdersManufacturing Techniques and Applications,

Stainless Steel Powders, pp.90-115

Iris Alvarez(2007, October 2) Duplex Stainless Steel: Brief History and Some Recent

Alloys Recent Patents on Mechanical Engineering,1,p. 51-57

OUTOKUMPU, 2010, November, Stainless steel for the food and drink industry, Available:

http://www.outokumpu.com/SiteCollectionDocuments/Stainless_for_food_and-drink-

Brochure.pdf(Accessed:2013, March 12)

Santonen,T., Stockmann,H., Zitting,A., 2010, Review on Toxicity of Stainless Steel, Finnish

Institute of Occupational Health, p.1-87

Tony Newson, 2003, Stainless Steel for Hygienic Applications, BSSA Conference: 2

V.Mohan , 2012, Hygienic importance of stainless steel in developing countries, International

Stainless Steel Forum: 1

V.W., 2013, A Brief History of Stainless Steels, Available:http://www.valve-

world.net/basicfacts/ShowPage.aspx?pageID=462 (Accessed:2013, March 11)

The New York Times, 1915, January 31, History of Stainless Steel Alloys, Available:

http://www.aerodynealloys.com/products/stainless/history.php (Accessed:2013, March 9)
http://www.outokumpu.com/SiteCollectionDocuments/Stainless_for_food_and-drink-Brochure.pdfhttp://www.outokumpu.com/SiteCollectionDocuments/Stainless_for_food_and-drink-Brochure.pdfhttp://www.valve-world.net/basicfacts/ShowPage.aspx?pageID=462http://www.valve-world.net/basicfacts/ShowPage.aspx?pageID=462http://www.valve-world.net/basicfacts/ShowPage.aspx?pageID=462http://www.aerodynealloys.com/products/stainless/history.phphttp://www.aerodynealloys.com/products/stainless/history.phphttp://www.valve-world.net/basicfacts/ShowPage.aspx?pageID=462http://www.valve-world.net/basicfacts/ShowPage.aspx?pageID=462http://www.outokumpu.com/SiteCollectionDocuments/Stainless_for_food_and-drink-Brochure.pdfhttp://www.outokumpu.com/SiteCollectionDocuments/Stainless_for_food_and-drink-Brochure.pdf


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