Stainless steels are steel alloys containing at least 10.5% Chromium (Cr) in its content.

The distinguishing feature of stainless steels is high corrosion resistance. Corrosion is an electrochemical process in which metals react with the environment.  Stainless steel is not a noble metal that can remain inert (does not react with the environment, does not corrode) in most environments such as, gold platinum rhodium.

Factor providing high corrosion resistance in stainless steels; When it comes into contact with air, a dense, ductile, very thin and transparent layer of chromium-oxide is formed on the surface of the material strongly adhered to the surface.  This very thin amorphous layer provides the necessary passivity and protects the internal and external structure against the chemical reactions and provides stainlessness.  Even if the material is processed while it is being used or the layer above it wears out, this layer has the feature of repairing itself and regaining its former feature.  This amorphous layer, which is also formed in materials such as Titanium (Ti) and Aluminum (Al), greatly increases the value of stainless steel.

This at least 10.5% Chromium (Cr) ratio added to the stainless steel ensures that the surface and internal structure of the steel resists against external factors and prevents rust.  Low alloyed types of stainless steel are suitable for atmospheric conditions and natural water; high alloyed types are resistant even to acids, alkaline solutions and chlorides.

In addition to their excellent corrosion resistance, stainless steels are available with varying mechanical properties.  Features are changed by adding or removing elements such as Carbon (C), Nickel (Ni), Molybdenum (Mo), Sulfur (S), Titanium (Ti), Copper (Cu), Vanadium (V), Niobium (Nb), Nitrogen (N), Wolfram (W), Mangan (Mn).

Chromium (Cr) is the leading element that provides corrosion resistance in stainless steels.  It is a ferrite stabilizing metal, so lean Fe-Cr alloys at room temperatures always have an internal structure with ferrite up to (20% Cr).  When chromium (Cr) exceeds 20% Cr, sigma phase starts.  Chromium (Cr) is a strong carbide builder.

Carbon (C) is an austenite stabilizing element.  It increases the yield strength and tensile strength and adds hardness and durability to the stainless steel material.

Nickel (Ni) is an austenite stabilizing element.  When Nickel (Ni) reaches 8%, the austenite zone expands well and the internal structure remains austenitic.  It greatly increases corrosion and oxidation resistance.  Increases strength and impact resistance at high or low temperatures.

Silisium (Si) increases oxidation resistance, it is necessarily included in heat resistant grades, it is a ferrite balancing element.

Aluminum (Al) is also used in heat resistant alloys and strengthens the effect of Silicium (Si).

Molybdenum (Mo) strengthens the passivity of stainless steel in acidic and chloride environments and increases corrosion resistance.

Wolfram (W) is a ferrite stabilizer and carbide builder. It is added to the alloy to increase the mechanical properties of the material.

Titanium (Ti) and Niobium (Nb) form very stable carbides, they are added to austenitic stainless steels to prevent sensitization.

Manganese (Mn) is also an austenite stabilizing element such as Nickel (Ni). Increases the strength and durability of stainless steel. In some qualities, Manganese (Mn) replaces Nickel (Ni) in order to reduce the cost.

Nitrogen (N) is basically an austenite stabilizing element and its effect is like Carbon (C). In order to reduce the cost, some austenitic stainless steels replace Nickel (Ni) when it is reduced.

Copper (Cu) is a weak austenite stabilizer. In some environments, it is added to the composition of austenitic stainless steels to increase corrosion resistance.

Sulfur (S) is added to increase the machinability of stainless steels. But it reduces the corrosion resistance and welding ability.

There are stainless steel types that can be used at low and high temperatures.  While standard austenitic stainless steel grades retain their properties up to 700 ° C, Nickel (Ni) and Chromium (Cr) amounts increased stainless steels’ heat resistances can increase up to 1150 ° C.  You can find detailed information about qualities in the Grades section of our website.  3AS stocks have materials suitable for all kinds of heat resistance.

There are types of stainless steels suitable for cutting, welding, hot and cold forming, reclamation and machining processes.  The usage areas of stainless steels have been diversified by adding or removing various elements mentioned above.  There is a different grade of stainless steel for almost every application. For the correct use of stainless steels, the most suitable stainless steel grade should be preferred.  Otherwise, the material will not give the desired result even if it is of a more qualified quality.  You can contact the 3AS team for the most suitable stainless steel quality according to the usage areas.

Thanks to the mechanical strengths of stainless steels, in places where normal steel materials are used, materials with lower diameters and thicknesses are used to reduce costs.  The use of the correct quality stainless steel is much more efficient than alternative materials, regardless of the field of use.  Although they are more expensive than steel in terms of price, they are materials that require low maintenance, cheap and easy to maintain, long lasting and durable.  The total life cost of the materials is low, so stainless steel is more economical than carbon steel in the long run.

The fact that stainless steels are hygienic and easy to clean causes these materials to appear frequently in the medical tools, kitchenware, household goods, food and medicine industries.  Stainless steel is an indispensable and a material with no alternative for these sectors.

Stainless steels come with many different surface options.  The aesthetic appearance of these surfaces and their easy maintenance are preferred for alternative materials.  Stainless steel materials can be surface treated as grinded, brushed, satiny and mirror.  Certain grades of stainless steel can polish up to mirror gloss.  Patterned surface can be given to stainless steel materials.  With these features, stainless steels appear in every area of decoration.

Stainless steels are environmentally friendly and fully recyclable materials.

Global trends such as population growth, urbanization, resource scarcity increase the need for long lasting and durable materials in the world.  The demand for stainless steel and the consumption of stainless steel are therefore increasing day by day.

AUSTENITIC STAINLESS STEELS

Austenitic stainless steels are chemical wear (corrosion) and high temperature resistant, containing a minimum of 10.5% to 26% Chromium (Cr) and Nickel (Ni) in amounts ranging from a minimum of 8% to 36% in their alloy.  Nickel (Ni) makes the steel structure completely austenitic. Nickel (Ni) gives the material ductility, possibility of working in wide temperature range and good weldability.

It has no magnetic properties. These alloys have excellent formability, corrosion resistance and weldability.  Due to the low Carbon (C) it contains, they cannot be subjected to heat treatment. The most known and used grades in stainless steels are in this group. It is the richest group in terms of number of different grades and proportion of alloy elements.

AISI 304 is the most used quality of stainless steel.  316 and 316L grades are obtained by adding (+) Nickel (Ni) and Molybdenum (Mo) to 304 Quality Steels.  In acidic environments, resistance to pointy corrosion is provided.  With the addition of Titanium (Ti), in 316Ti grade, higher mechanical strength is obtained at higher temperatures than 316L quality.  In 321 grade stainless steel, higher temperature resistance and higher abrasion resistance were achieved by increasing the nickel (Ni), adding Titanium (Ti) and decreasing Carbon (C) to the chemical composition of 304.

Stainless steel thermal conductivity is 10 times lower than aluminum and 4 times lower than steel. The transmission of cold from outside to inside is low on the exterior construction.

The "L" extension at the end of the grades (such as 304L, 316L) means that the Carbon (C) in it is reduced and the welding ability is increased by softening the material.  They have good shaping properties even in cold condition.

Austenitic Steels have a flexible and tight internal structure. Welding connections are suitable since they do not harden in heat environments due to the low Carbon (C) ratio in their alloys.  On the other hand, since the heat conduction is low and the expansion is high, the heat input should be kept low to prevent bending or warping of the material at the source.

Austenitics are generally found in Bar, Flat, Hexagonal, Angle, Square, Corner, Coil, Sheet, Strip, Pipe, Profile, Screen Wire, Fittings forms.  Within 3AS, you can find austenics in Stick, Flat, Angle, Hexagonal, Square, Coil, Sheet, Strip, Pipe, Profile, Screen Wire forms from ready stock.

MARTENSITIC STAINLESS STEELS

Martensitic stainless steels contain between 12.5 - 18% Chrome (Cr) and 0.10 to 1% Carbon (C). These alloys can be used in a wide range, they can be heat treated to achieve high hardness levels.

The entire martensitic group is magnetic.

AISI 420 quality is the most used quality of the group. Almost all of the martensitic group, except AISI 410, can be hardened by heat treatment.  Hardening feature of martensitic group; Ideal for use in places where high tensile - friction - fatigue resistance is required.  The lowest carbon content is found in AISI 410 quality and it is found rarely in our country and almost only in sheet format.

AISI 431 quality is increasingly preferred due to its improved corrosion resistance thanks to the addition of nickel. It is also possible to harden this quality with heat treatment.

After heat treatment, they can get hardness grades from 45 to 60 Rockwell. If the carbon content is below 0.17%, the material hardness does not exceed 45 Rockwell. As the Carbon (C) ratio in the material decreases, the hardness (Rockwell) ratio after heat treatment decreases.

They are moderately corrosive. It can be used in applications up to 400 ° C. If the temperature rises above 650 ° C, the material structure will deteriorate.

It is offered to the market in Annealed or Improved condition depending on the product type. The products taken as annealed are subjected to the treatment process (quenching + tempering) after shaping.  Different combinations of properties are obtained by changing the temperature of tempering.  In order to obtain the best corrosion resistance, it is very important to follow the recommended heat treatment temperatures precisely. The welding ability of this group is very low, and this group is not found in the form of material pipes.

FERRITIC STAINLESS STEELS

Ferritic stainless steels are low carbon and stainless steels containing 11-30% Chrome (Cr). The main alloying element in this group is Chrome (Cr) followed by Molybdenum (Mo). The entire ferritic group is magnetic. The most used type is 430 quality.

They are similar in structure to mild steels, but their corrosion resistance is high. Among them, a minimum of 11% to a maximum of 30% Chrome (Cr) and a small amount of austenite elements such as Carbon (C), Nitrogen (N), Nickel (Ni) are added.

Ferritic group has low impact resistance and weldability. The lowness of these properties means that the fragility of the material is high. For this reason, their use as machine parts especially for welded assemblies and thick sections is limited. They cannot be shaped as easily as austenitic steels.

Ferritic grades have low thermal expansion, high thermal permeability and high yield resistance.

Some usage areas of this group are automobile chassis and exhaust parts, some kitchen equipment, hot water tanks, washing machine drums, air conditioning channels, barbecue grills. Their resistance to atmospheric corrosion and oxidation are their important advantages.

Since the ferritic group contains low Carbon (C) in its content, it cannot be hardened by heat treatment, it is used only in the annealed condition. The medium to good corrosion resistance of ferritic steels improves in direct proportion with the increase in the amount of Chromium (Cr) in their chemical composition.

Ferritics are divided into 3 main groups according to the chromium (Cr) ratio:

Chromium amount between 11 - 13%: (409, 410S, 1.4003 grades) In the first group with low chromium ratio, it has low oxidation and corrosion resistance as well as low price and good manufacturing properties. The most used of this group used in automotive exhaust parts is 409 grade.

Chromium amount between 14 - 18%: (430, 434, 436, 439, 430Ti, 441, 444 grades) These are grades with medium chrome and low impact resistance and welding ability used in the production of automotive parts and kitchen appliances. In this group, extra corrosion resistance is provided by adding Molybdenum (Mo) to some grades.

Chromium amount between 19 - 30% (Super Ferritics): (442 and 446 grades) This group is examined separately from Ferritic grades, they are special grades. They are preferred in places where high corrosion and oxidation resistance is required.

Ferritic grades are lower cost than Austenitic materials. For this reason, they are preferred in situations that will not cause problems in product and application if used. The fact that ferritic grades are magnetic reduces their preferability compared to austenitic grades, but in some application areas this disadvantage turns into an advantage. An example of this is that the built-in refrigerator is magnetic.

Compared to carbon steel, Ferritic group has all the advantages of Stainless Steel such as corrosion resistance, low total life cost, longevity, aesthetic appeal.

Ferritics are generally available in Bar, Sheet and Welded Pipe forms. In the 3AS stock portfolio, you can find the ferritics from ready stock in Bar, Coil and Sheet forms. There are stocks of 430, 409, 410S and 1.4003 grades on coils and sheets, and 430L and 430F grades on bars.

DUPLEX STAINLESS STEELS

The microstructure of duplex (Duplex) stainless steels consists of austenite and ferrite mixture.

They are steels containing high amount of Chromium (Cr) from 16% to 28%, 4.5 to 8% medium amount of Nickel (Ni), 2.5 to 5% Molybdenum (Mo).  The most used qualities of the duplex group are 1.4462 and 1.4362.

Due to their internal structure, they have both good strength and good corrosion resistance at the same time. The amount of Nickel (Ni) in its content is at most 8% and this rate is insufficient for the whole internal structure to be austenitic. This highly alloyed stainless steel group, consisting of almost equal amounts of Ferrite and Austenite phases, is called Duplex.

At the same time, they are both ferritic and have an austenitic structure; It maintains its magnetism and provides high mechanical properties and high corrosion resistance.

Tensile corrosion resistance is very high. It has higher mechanical strength than austenitic and ferritic steels. High molybdenum in its content provides longer durability than 316 series in acidic and marine environments.

They have better tensile corrosion than austenitic stainless steels and better tensile strength than ferritic stainless steels. It has very suitable fatigue strength in corrosive environments. They are magnetic and cannot be hardened by heat treatment.

They are used in medium temperatures, heat exchangers, petrochemical plants, marine and salt water environments, chemical apparatus manufacturing, purification facilities and oil platforms.

PRECIPITATION HARDENING GROUP

This group, known as PH steel, means precipitation hardening and comes from the term "precipitation hardening" in English.

This group has 3 types with austenite, semi-austenite and martensite. All of them are hardened by aging processes. General feature of these 3 groups; medium-good corrosion resistance and very good mechanical properties.

These materials generally have moderate to hard workability. In addition, the general feature of these materials is that they all have a magnetic structure.

Precipitate hardening can be applied to these steels and despite low Carbon (C) ratios, they can reach up to 44 HRC hardness. Aluminum (Al), Titanium (Ti), Niobium (Nb) and Copper (Cu) elements are added to provide precipitate formation.

These steels have good flexibility and tensile strength, medium to good corrosion resistance. However, their abrasion resistance is not very good.

It is used in environments requiring high strength / weight ratio and corrosion resistance in aircraft, defense, space industry.

STAINLESS STEEL COIL

Stainless steel coil is one of the most common shapes of stainless steel.  Stainless steel flat materials are usually produced in rolls up to 12 mm thick.

These materials can be used as rolls and can be personalized according to the need by passing through straightening and length cutting, slitting or grinding processes in the high prestige process lines in our service center.

In the Cut To Length Line, the materials are cut to the desired length after passing through the levelers (rectifier) to gain linearity.  In the meantime, paper or PVC coating can be applied to the material.  Thus, materials provided in the length requested by the customer instead of standard sizes and material waste is prevented.

Contrary to the above-mentioned length cut, the slitting line is cut from the width. Thus, the desired width of the coil is reached. In the slitting line, even a few mm of edge cutting, as well as narrow coils or strips with a width as narrow as 10 mm can be made in 3AS Service Center.  In the meantime, paper or PVC coating can be applied to the material.  In sheet form, after slitting, length cutting or even grinding processes can be applied and material can be supplied in accordance with customer's demand. Thus, materials provided in the width requested by the customer instead of standard sizes and material waste is prevented.

In the Grinding Line, brushed surfaces are obtained by applying surface grinding to flat materials with 2B or BA surfaces. In the meantime, paper or PVC coating can be applied to the material. The most frequently encountered grinding applications are the No4 and Scotch Brite surfaces. Unlike the 2B matt surface, which is skinpass applied on cold rolled and annealed material, grinded surfaces are preferred more often in decoration and especially in built-in products.

Stainless steel rolls are available in 3AS stocks with a wide variety of grades and in all commercial sizes that are produced. Our service center and processing lines are physically conveniently planned and implemented to ensure that all stainless steel rolls produced in the world are suitable for our customer’s demands. This means that any stainless steel rolls that can be physically produced can be supplied via 3AS.

STAINLESS STEEL SHEET

Stainless steel plate (Stainless steel sheet) is the most common form of stainless steel.  Stainless steel flat materials are usually produced in coil form up to 12 mm thickness.  Production is made in plate form after 14 mm of thickness.  All sizes of stainless steel can be turned into a plate by cutting from roll to length and slitting if necessary.  All types of stainless steel can be turned into sheets in desired sizes to be offered for sale by cutting and slitting from the coil.

In our Stainless Steel Service Center, the width, length and surfaces of the plates can be personalized according to the needs by processing stainless steel through cut-to-length, slitting or grinding and brushing lines.

In the Cut To Length Line, the materials are cut to the desired length after passing through the levelers (rectifier) to gain linearity.  In the meantime, paper or PVC coating can be applied to the material.  Thus, materials provided in the length requested by the customer instead of standard sizes and material waste is prevented.

Contrary to the above-mentioned length cut, the slitting line is cut from the width. Thus, the desired width of the coil is reached. In the slitting line, even a few mm of edge cutting, as well as narrow coils or strips with a width as narrow as 10 mm can be made in 3AS Service Center.  In the meantime, paper or PVC coating can be applied to the material.  In sheet form, after slitting, length cutting or even grinding processes can be applied and material can be supplied in accordance with customer's demand. Thus, materials provided in the width requested by the customer instead of standard sizes and material waste is prevented.

In the Grinding Line, brushed surfaces are obtained by applying surface grinding to flat materials with 2B or BA surfaces. In the meantime, paper or PVC coating can be applied to the material. The most frequently encountered grinding applications are the No4 and Scotch Brite surfaces. Unlike the 2B matt surface, which is skinpass applied on cold rolled and annealed material, grinded surfaces are preferred more often in decoration and especially in built-in products.

Stainless steel sheets are available in 3AS stocks with a wide variety of grades and in all commercial sizes that are produced. Our service center and processing lines are physically conveniently planned and implemented to ensure that all stainless steel sheets produced in the world are suitable for our customer’s demands. This means that any stainless steel sheets that can be physically produced can be supplied via 3AS.

STAINLESS STEEL BAR

Stainless steel bar is the most used material in the stainless steel long group. The bar is the name given to the materials with a round cross section, if the material is shaped, it can take names such as four-corner bar, hexagonal bar.

The production range of stainless steel bars is physically minimum Ø2 mm. The maximum diameter is up to Ø1000 mm, but commercially available sizes are up to Ø500 mm. Stainless steel bars are available in austenitic, martensitic, ferritic and duplex grades in our stocks, together with special grades even though their use is uncommon.

STAINLESS STEEL FLAT BAR

Stainless steel flat bar is the name given to the rectangular section filled material in the stainless steel long products group. It is one of the two varieties found between full materials with a section of 90 degrees. The other material is the four corners that appear when the section sizes are the same.

The production range of stainless steel flat bar is physically minimum 10x5 mm.  Stainless steel flat bars are produced cold rolled in sizes such as 10x5mm, 15x5mm and 15x10mm.  Production flat bars greater that 20x3 mm are commercially available in hot rolled, annealed and acidified (HRAP) condition.  Maximum size can reach up to 200x50 mm, but commercially available sizes are up to 150x40 mm.  Stainless steel flat bars are available in austenitic grades in our stocks, together with special grades even though the use of these grades is not common.

STAINLESS STEEL ANGLE

Stainless steel angle is the name given to the filled material with “L” section in the stainless steel long products group.  U or I sectional shapes of such materials are also produced in the world.

Stainless steel angle production range is physically minimum 20x20x3 mm.  Stainless steel brackets are available in all sizes of hot rolled, annealed and acidified (HRAP) condition.  Maximum sizes are up to 300x300x20 mm, but commercially available sizes are up to 100x100X10 mm.  Stainless steel brackets are available in austenitic grades in our stocks, together with special grades even though the use of these grades is not common.

STAINLESS STEEL WIRE

Stainless steel wire is a material sold in bundles in the stainless steel long products group.

The production range of stainless steel wires can be wound up to micron levels. The maximum diameter is up to Ø15 mm, but commercially available sizes range from Ø1 to 12 mm.  Stainless steel wires are available in austenitic and ferritic grades in our stocks, together with special grades even though the use of these grades is not common.

STAINLESS STEEL SQUARE BAR

Stainless steel square bar is the name given to the filled material with square cross-section in the stainless steel long group.  It is one of the two varieties found among full materials with a section of 90 degrees.  The other material is flat bar materials, which appear when the cross-sectional dimensions are different.

The production range of stainless steel square bars is physically minimum 4x4 mm. Stainless steel square bars are produced as cold drawn.  Stainless steel square bars are available in austenitic grades in our stocks, together with special grades even though the use of these grades is not common.

STAINLESS STEEL HEXAGONAL BAR

Stainless steel hexagon is the name given to the filled material with hexagonal cross section in the stainless steel long group.

Production range of stainless steel hexagonal bars is physically minimum SW 4 mm.  Maximum dimensions increase up to SW 75 mm.  Stainless steel hexagonal materials are produced as cold rolled.  Stainless steel hexagonal bars are available in austenitic grades in our stocks, together with special grades even though the use of these grades is not common.

STAINLESS STEEL PIPE

Stainless steel pipe is one of the unfilled (hollow) materials in the stainless steel long group. Round section form is called pipe, square or rectangular sections are called profiles.

Stainless steel pipes are divided into two as welded and seamless. The production process of these two products is completely different.  The more common use is welded pipes.  Welded pipes are produced by welding from strip sheets.  HF, Laser or TIG welding are the most common welding methods according to the usage areas of pipes.   While decoration pipes and profiles are produced by HF (High Frequency) method, industrial pipes are produced by TIG (Tungsten Inert Gas) or Laser welding.

Commercial size range of stainless steel welded pipes ranges from 12x1 mm to 323.9x4 mm. However, it is possible to produce many standard and non-standard sizes in pipes.  Stainless steel pipes can be produced with raw, brushed, satin or glossy surfaces according to their usage areas.

STAINLESS STEEL PROFILE

Stainless steel pipe is one of the unfilled (hollow) materials in the stainless steel long group. Round section form is called pipe, square or rectangular sections are called profiles.

Stainless steel profiles are produced by welding.  Welded profiles are produced from slitting sheets (strip) by HF welding.  Profiles are also called square profile or rectangular profile according to their cross-section.

The commercial size of stainless steel profiles is in the range of 10x10x1 - 150x150x5 mm.  However, it is possible to produce many standard and non-standard sizes in welded profiles.  Stainless steel profiles can be produced with raw, brushed, satin or glossy surfaces according to their usage areas.

AISI (AMERICAN IRON AND STEEL INSTITUTE): USA

EN (EUROPEAN NORMS): EUROPE

DIN (DEUTSCHES INSTITUT FUR NORMUNG): GERMANY

AFNOR (ASSOCIATION FRANCAISE DE NORMALISATION): FRANCE

BSI (BRITISH STANDARDS INSTITUTION): UK

JIS (JAPANESE INDUSTRIAL STANDARDS): JAPAN

UNI (ENTE NAZIONALE ITALIANO DI UNIFICAZIONE): ITALY

GOST (GOSUDARSTVENNYY STANDART): RUSSIA

Points to be considered in Stainless Steel manufacturing:

Stainless Steel materials and Carbon Steels should not be kept in the same environment and in contact with each other, and if possible, their manufacture should be carried out in different environments.

If care is not taken during the manufacturing process, the material surface can be scratched or crushed with the surrounding Carbon Steel materials. As a result of such damage, the protective oxide layer on the surface of stainless steels is eliminated. These regions become sensitive to oxidation. For this reason, it should be stored on heavy wood material. Do not use any elements that may damage the material surface, such as chin carriers, ropes and chains.

If it is going to be manufactured for decorative purposes, the materials covered with foil (PE or PVC) should be used.  Cutting and bending process is applied to these materials when the material is covered with foil.  The purpose of the foil is to prevent surface damage that may occur in the production process.  When the production process is completed the foil can be easily removed from the assembled parts to obtain the desired clean surface.

During cold forming of stainless steels with presses, the material is processed using Cold Work Tool Steels. Both Stainless Steel and Carbon Steel material should not be processed with the same mold. If it must be processed, Stainless Steel material can be processed after the mold parts are cleaned with chemicals.

Points to be Considered in Cutting - Drilling Process:

During the cutting and drilling process in the mold, a gap of 7-10% of the material thickness should be given between the upper and lower cutters.

237 or powder metallurgy steels should be used. HSS punch pins should be used for Stainless Steel drilling.

Especially if stainless steel material is to be cut on the guillotine shear, the blades and the surface that the material will contact should be cleaned very well with chemicals.

Points to consider in Stainless Steel Bending Process:

When the Stainless Steel Plate materials are bent at an angle in the bending press, eccentric press or hydraulic press, friction occurs between the bending die and the material.  For this reason, the bending molds on which this process is performed must be made of stainless steel material.

If there is no possibility of molding from Stainless Steel materials and if molds such as 1050, 1060 are available, the Iron (Fe) element in the mold must be plastered in parts that are invisible size from the surface of the Stainless Steel.

If these parts are not removed from the material surface, these particles adhering to the Stainless Steel surface will oxidize after a certain period of time.  After that, the surface of the material is covered with rust stains (parts contacted with the mold).  Thus, the quality of Stainless Steel may no longer be indisputable.  In order to avoid all these problems, if Stainless Steel materials are bent and formed with mold materials such as 1050, 1060, they must be cleaned with special Stainless Steel chemicals after the process.

Points to be Considered in Stainless Steels Welding Process:

Similar rules should be followed in welding process of Stainless Steel materials.

There should be no rust dusts or Carbon Steel dusts in the welding environment of Stainless Steel.

While welding Stainless Steel parts, the parts to be welded should definitely be welded on a Stainless Steel plate.

If the welding is made on a plate containing carbon, because of the arc that will form between the part and the material, particles of the carbon plate material are adhered to the Stainless Steel material through the arc way. This can then be seen as rust spots.

During the welding process of the Stainless Steel material, the plate, hammer and brush must be made of Stainless Steel material. If grinding is going to be done after welding, the grinding stone must be suitable for Stainless Steel material.

If the hammer, brush and grinding stone is made from the materials used for unalloyed carbon steels, after a certain time following the manufacturing process there will be discernable rust (Iron (Fe) particles on which the unsuitable elements are left on the Stainless Steel material) will appear on the welded area grinded surfaces.

In order to avoid all this, after welding, the stainless steel must be cleaned from particles that have been plastered or submerged on its surface. Even though there are chemicals to clean the plastered or submerged particles and to remove them from the surface, it is possible to clean with a 20% nitric acid solution by immersing the welded piece in this solution at 5 ° C - 60 ° C.

Other Suggestions

In machining:

ISO M10 - M20 quality hard metal inserts should be used and special cutting oil with 100% purity should be used as coolant.

In milling process:

ISO K01 - K10 quality hard metal inserts should be used.

Cold forging - Reduction:

AISI 304L / AISI 316L should be preferred instead of AISI 304 / AISI 316 in such difficult operations.

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