18-8 Stainless steel is a type of austenitic stainless steel that contains approximately 18% chromium and 8% nickel. K-factor (centrifugation), relative pelleting efficiency. 4301 and 1. To perform the calculations, we will need to obtain 4 parameters. If we know the Reynolds number and the roughness - the friction coefficient - λ - in the particular flow can be calculated. Pressing / Drawing. 8 Bare Steel; DIN 7984-10. 8×12. Radius Thickness. AISI 316L stainless steel is an modified ultra-low carbon austenitic stainless steel properties, composition, tensile yield strength. Cold Rolled Steel. On the one hand, 304 SS can handle heat well. 3 9. We stock one of the most extensive inventories for stainless steel products & are. 5%) metals as the main non-iron constituents. 2. 0mm R1 12v 0. Grade 304 stainless steel is generally regarded as the most common austenitic stainless steel. 286 lb/in3). For standard bolt torques use 0. Type 304 is the most versatile and widely used stainless steel. 304/304L demonstrates excellent corrosion resistance. p = 2 (0. As the cost of alloys changes daily on the global market, this can have a large impact on the price fluctuations. Austenitic grades; AISI 304 and 316 in annealed condition. 4 Btu/ft·h·°F at 212 °F), tensile strength is 515 MPa (75 ksi), yield strength is 205 MPa (30 ksi). For this dose range, the surface roughness factor for 304 SS is significantly higher than for 316 SS. inl. material and thickness. The students are made aware of the fact that Paris Law is applicable for stress intensity factor range higher than the threshold value ΔK thGrade 304 Stainless Steel is an amazingly versatile material with countless uses. 01 × G A M F) KC1. DIN 84 Slotted Cheese Head A2 Stainless; DIN 963 Slotted Flat Countersunk A2 Stainless; DIN 965 Phillips Flat Countersunk A2 Stainless Steel; DIN. Apps can be a great way to help learners with their math. Morton, S. Stainless steel grade 304N has better corrosion resistance than grade 302, and is mostly non-magnetic in nature; however when cold worked it acquires a slightly magnetic quality. . S. Hot rolled steel: 0. Stainless steel grade 430 is capable of resisting oxidation up to 870°C (1598°F) in intermittent usage, and up to 815°C (1499°F) in continuous usage. Below is a chemical breakdown of 304 steel: <=0. Sustainable building with Stainless steel - The David L. 43 Pounds. Stainless Steel 304 & 305 Ulbrich Stainless Steels & Special Metals, Inc. The range of Machinability is vast and spans from about 40% for difficult to machine steels, such as bearing steel ( SAE 52100 / DIN 100Cr6) up to Ledloy free-cutting steel (SAE 12L14 / DIN 9SMnPb36) that has a machinability rate of about 170%. (2023). D. All stainless steels share a minimum percentage of 10. 4. 345-74% iron <= 2% manganese; 8. Box 1625 Idaho Falls, Idaho 83415-3760 United States of America (208) 526-9354, robert. 4 Btu/ft·h·°F at 212 °F), tensile strength is 515 MPa (75 ksi), yield strength is 205 MPa (30 ksi). The range of Machinability is vast and spans from about 40% for difficult to machine steels, such as bearing steel ( SAE 52100 / DIN 100Cr6) up to Ledloy free-cutting steel (SAE 12L14 / DIN 9SMnPb36) that has a machinability rate of about 170%. 61 Polished Sheet 100 (38) . It is a general term for stainless acid-resistant steel, which resists corrosion from atmospheric, acid, alkali, salt, and other media. 26 1. Linear thermal expansion coefficient (α) at 20°C for Stainless steel. 000. Austenitic grades are the most commonly used and accounts for more than 70% of production with type 304 the most common. Red Flag This Post. 93 g/cm3 (0. One disadvantage of 304 is that it is non-hardenable by heat treatment. Applications. 4307 are also known as grades 304 and 304L respectively. The welding of stainless steel pipe sections must be performed by skilled technicians, and in accordance with the standards prescribed. MR Direct 4521 Triple Bowl Stainless Steel. This article discusses the properties and applications of stainless steel grade 304 (UNS S30400). S. Stainless Steel: 304ss, 316ss, 410ss. AISI 304 – industrially denoted as 18/8, is an austenitic chromium-nickel stainless steel. 08 Steel, Oxidized 77 (25) . Note that the emissivity coefficients for some products varies with the temperature. 433 0. , of high grade SS materials). The softer, high ductility austenitic types, such as 304 and 316, can suffer from galling and, in extreme cases. Stainless Steel. 33: K factor:. Rp490. K. Hsu, T. The k-factor can be calculated from the bend allowance. 93 g/cm3, which equals 0. • Standard Stainless Steel Screens OPTIONS • Perforated Stainless Steel Screens - 1/32" to 1/2" • 20, 40, 60, 80, 100, 150, 200, 325 and 400 Mesh Stainless Steel Screens • Monel Screens • 1⁄4" to 10" • Carbon Steel and Stainless Steel • Threaded, Flanged & Socket Weld Connections Cross-section of a Y Strainer with blow off. Stainless Steel 404. 2. The best known grade is AISI 304 stainless, which contains both chromium (between 15% and 20%) and nickel (between 2% and 10. Thermodynamics Work, heat and energy systems. Actually there are over 50 stainless steel alloys. Defining the Neutral Axis To understand the k-factor,. A comparison of the surface roughness factor (SRF), determined by xenon adsorption, has been made for the surfaces of 304 and 316 stainless steels irradiated with 100 keV helium ions. AISI 304 and 316 are the most common grades in this series. Surface Emissivity Coefficients. Bushing for chain. 200!K, Table 3. picked a sample of The coupled-environmental fracture model (CEFM) for intergranular stress corrosion cracking (IGSCC) of sensitized type 304 stainless steel in light-water reactor (LWR) heat-transport circuits was extended by incorporating steel corrosion, hydrogen oxidation, and hydrogen peroxide reduction in addition to oxygen reduction as charge-transfer reactions occurring on the external surfaces. The wear against anodized aluminum is equivalent to that with the carbon steel, while cast iron and stainless steel seem to double the wear rate. 304L can, therefore, be used "as welded" in severe corrosion environments, and it eliminates the need for. 4301) is a widely-used austenitic chromium-nickel stainless steel. 61 Polished Sheet 100 (38) . However, continuous use at 425-860°C is not recommended if corrosion resistance in water is required. Introduction American Iron and Steel Institute (AISI) type 304 is the foundation of 300 series austenitic stainless steels is by far the oldest, largest and most important group in the stainless steel range [1]. Type 304L stainless steel is an extra-low carbon version of the 304 steel alloy. 55 to 1mm R1 10v 0. 0. The weight of stainless steel per cubic inch is 0. Low carbon content means less carbide precipitation in the heat-affected zone during welding and a. The density of stainless steel is about 7. 27 mm ) 0. 86-Rubber (60 A Belt). 5% is ideal. 10" 1000 (538) . 4404 35N -1. 345-74% iron <= 2% manganese; 8. 120" 0. Type 304 stainless steel is an. 4. The torque values are approved for spiral wound graphite. 3236. 030. 8 mm bend radius has a springback of 0. 1. The absence of nickel in 430 means that this grade of stainless steel will likely crack or fail if compared to pressing 304. Stainless steel 304 (EN steel number 1. LBS 2350 3900 5750 7850 10500 16700 PROOF LOAD, LBS 3800 6300 17000 27100 TENSILEASME B16. The K-factor is calculated based on value ranges and is used to determine the following: Tube bending feasibility (whether it is in fact possible to bend a round, square or rectangular tube) Predicted difficulty. It has high strength, moderate corrosion resistance, and good hardness and wear resistance. MATERIAL, BEND RADII AND MINIMUM BEND SIZE CHARTS. It is, however, rarely used. 3. by：East King 2020-08-30. It is still sometimes referred to by its old name 18/8 which is derived from the nominal composition of type 304 being 18% chromium and 8% nickel. Our bend radius rule of thumb is the minimum radius = material thickness. Find linear thermal expansion coefficient (α) and volumetric coefficient for thermal expansion (β) at 20°C for different material like brass, copper, concrete, lead, silver, water and more. 10" 1000 (538) . ₹ 145 / Kg. Conductivity in Aluminum. 1. For instance, austenitic stainless steels like AISI 304 and 316 exhibit exceptional corrosion resistance and typically deliver smoother surfaces compared to other. Linear thermal expansison coefficients of metals and alloys (Cont. Abstract. The test specimens were cut out of a single plate of either 304 or 304L stainless steel to dimensions of 152. Please let us know here why this post is. As a leader in price assessments, CRU releases monthly prices for chrome. The 𝜎 phase can precipitate. 304 is one of the easier austenitic stainless steels to forge, at temperatures above 925°C. Drawn Brass, Copper, Stainless Steel (New) >0. The 1. 304. These are 304 SS material. The K-factor also increases with harder materials such. However, grade 410 steels are less corrosion resistant than austenitic grades and grade 430 ferritic alloys containing 17% chromium. 304 stainless steel is one of the most popular types of stainless steel. Different substances expand by different amounts. 4301 S30403/EN 1. 5% nickel whereas 430 contains 0%. A 304 Stainless Steel similar to the Class 1, but has been carbide solution treated and strain-hardened. 301, 302, 304, and 316 austenitic stainless steels. 0 % flow stress. However, continuous use at a temperature between 797-1580 °F can lead to corrosion. If the aluminum is not anodized, the wear rate is extremely severe. The quality of welded joints was. The quality of the water regarding the health and safety of consumers is a matter of the utmost importance in the urban water-consuming system [3,. Thermal Conductivity - k - is the quantity of heat transmitted due to an unit temperature gradient, in unit time under steady conditions in a direction normal to a surface of the unit area. Stainless Steel Prices/Nickel Prices. Achieving Proper Bolt Torque: An Introduction to K-Factor. Rod end bearing. 5 in) - 2 (0. This stainless steel grade shows good ductility in the annealed condition, and can be readily drawn and formed. Stainless steel grade 301 is usually supplied in the form of strips and wires, with a tensile strength of up to 1800 Mpa, to produce tempers ranging from 1/16 Hard to Full Hard. Melting Range: 2550-2650°F (1399-1454°C) We offer a wide range of 304 stainless steel options to meet your various needs. Typical uses of 304 stainless steel include sinks, kitchen equipment such as pans, tubing and much more. Product Code: SSH-1. 5. Inside temperature. Chemical. Stainless steel 304 and stainless steel 304L are also known as 1. Notes: 10 -6 ·K -1 = 10 -6 /K 1 Ω·mm²/m = 1 μΩ·m 1 g/cm3 = 1 kg/dm3 = 1000 kg/m3 1 GPa = 1 kN/mm2 K °F: Latent Heat of Fusion: 260: 285: kJ/kg: 111. The most common form of 304 stainless steel is 18-8 (18/8) stainless. Datasheet-3: The following table lists 1. Melting Range: 2550-2650°F (1399-1454°C) We offer a wide range of 304 stainless steel options to meet your various needs. 28 Steel, Unoxidized 212 (100) . If you are only estimates, according to common steel density 7. 73: 1696. They are: 1. Source: STEEL PRODUCTS MANUAL, STAINLESS AND HEAT RE-SISTING STEELS, DECEMBER 1974, American Iron and Our market analysis draws on our multi-commodity capabilities across nickel, ferroalloys and steel to provide an in-depth examination of stainless steel flat products globally. If a material is 0. The heat transfer convection coefficient for air is 50 W/m 2 K. 453 0. The corrosion resistance of stainless steels means that the surface characteristics, including frictional properties, are unlikely to be affected in service due to corrosion issues, provided the correct grade has been selected. The most common grade of austenitic stainless steel is 304 (1. 463 0. Stainless steel grade 304 is the most commonly used stainless steel. Recently, the probability-based Load and Resistance Factor Design (LRFD) criteria have been successfully applied to the structural design of hot-rolled. 07" 500 (260) . 3: Steel Stainless Austenitic (310) 14. 2. JINDAL L Shape Stainless Steel Angle, For Industrial. 3) X10-6 m/ (m °C). 50 in practical use. Stainless Steel is all around us, it is used for benches, tapware, ovens, rangehoods. stainless steel with good general corrosion resistance. 5. Low-carbon steel (annealed) 0. VK Number: VK630. ASTM A193/A193M B8M Class 1 All 75,000 30,000 B96 A 316 Stainless Steel used for high temperature applications. 063” | 1. 67. 1. 304 stainless steel yield strength at 0. 420 0. Page: F_102905. Their composition is given in Table 1. Nature of the grain boundary and stress corrosion cracking (SCC) The grain boundary energy in type 304 stainless steel is known ( Murr 1975) to vary from 20 to 835 mJ/m 2. Just select a k factor according to your material from the table below. As a guideline the emmisivities below are based on temperature 300 K. (10-6 in/ (in oF)) Admiralty Brass. 93 g/cm3 (0. Davis. Thermal conductivity of stainless steel 316, (W/m·K) 12. Essentially non-magnetic, becomes slightly magnetic when cold worked. Dry Torque) Partially Lubricated Bolts; Properly Lubricated Bolts; But before we talk about these items, or get to our torque chart, it is imperative you understand the working definition of K-Factor (or “Nut Factor”). To understand how the nut factor compares to the terms in the long-form equations, let’s consider the so-called Motosh equation: × [ (P/2 ) + (μ/cos ) + (μ = input torque, = fastener preload. AISI 304 stainless steel (UNS S30400) is the most commonly used material in stainless steels, and is usually purchased in an annealed or cold worked state. After reading this article, if you still have confused about Carbon Steel and Stainless Steel. 5. It is the most versatile and most widely used stainless steel available, even though a wide range of alternatives are available; and has excellent forming and welding characteristics. Mathematically k factor value is equal to the ratio of position of neutral axis and sheet thickness. --bend allowance less than 90 degrees. 14 × 10 17 MPa −1 s −1. Advantages/Disadvantages. 304 Stainless Sheet offers good corrosion resistance to many chemical corrodents as well as industrial atmospheres and marine environments. INTRODUCTION In 1983, Bogaard [1 ] presented a paper on the thermal conductivity (2) of AISI 304 stainless steel (SS) between 100 and 1707 K. The K-factor can also be used to calculate bending allowance and bending deduction. 5% chromium content by mass. 4401/1. 459. K-Factor Rating (Harmonic Mitigation): K-1 (Standard) External Non-PCB Label Pulse Drive Rating: N/A External Barcode Label. Text is available under the Creative Commons. e. The K-Factor is a property of the material being bent. Stainless Steel: CF8 (304), CF3 (304L), CK20 (310), CF8M (316), CF3M (316L), A297 Heat Resistant, A351. Ferrite Structural Steels Private Limited. This article summarizes the thermal conductivity of stainless steel 304 and 316 at various temperatures in annealed condition, also other stainless steel grades. At 80 K, the emissivity of the undamaged silver coating was found to be 0. 8 Lock Washer ASTM A276 304 Stainless Steel 9 Stem Washer ASTM A276 304 Stainless Steel 10 Diaphragm Washer ASTM A536 65-45-12 Epoxy Coated Ductile Iron 11 Diaphragm* Buna-N (Nitrile) 12 Disc Retainer ASTM A536 65-45-12 Epoxy Coated Ductile Iron 13 Seat Disc* Buna-N (Nitrile) 14 Spacer Washer* x5 NY300 Fiber* 15 Disc Guide. To achieve stainless corrosion resistance, the amount of chromium (Cr) should not be less than 13%. 17. 4401 and 1. 1 A36 Steel 3/8” less than 50 53. 12 Mild Steel, Liquid 2910-3270 (1599-1793) . Download the free PDF here. 4307 are also known as grades 304 and 304L respectively. 5389. 8 Square Head; Low Head Socket Cap Screws. 7 6061-T6 Aluminum 1/2" between 60-65 41. The low carbon chemistry of 304LReference is often made to stainless steel in the singular sense as if it were one material. 1 is normalized to 1 mm at 0° rake, we need to calculate the actual specific cutting force KC coefficient suitable for our conditions. Conductive Heat Transfer through a Stainless Steel Pot Wall with thickness 2 mm - temperature difference 80 o C. If you have a project that needs to stand the test of time, stainless steel is a great choice. Stainless steel grade 430 is capable of resisting oxidation up to 870°C (1598°F) in intermittent usage, and up to 815°C (1499°F) in continuous usage. Th e GTA welds wer produced at th e author's laboratory, whil th SAAbstract and Figures. The results shown in Fig. Bolting torque to develop 50% Bolt Yield Stress at Nut Factor, K=0. Better corrosion resistance than Type 302. By subjecting grade 301 to controlled analysis it is capable of retaining sufficient ductility even in ½ hard conditions. 304 stainless steel, and the filler metal was Type 308 stainless steel. 307 respectively. This means that the neutral axis cannot migrate past the midpoint of the material (i. Effect of low-temperature on mechanical behavior for an AISI 304 austenitic stainless steel. Clear. 463 0. 304 Stainless Sheet may become slightly magnetic when worked and is not heat treatable. 45 The K-factor is also referred to as the neutral layer position factor. 304. They withstand washdowns with harsh cleaners and sanitizers. Stainless steel 304 and 304L are also known as stainless steel 1. One cubic meter of 304 stainless steel weighs 7,930 kg. EN 1. The K-factor is used to determine the length of the metal plate stretched during the bending process. This issue can be overcome with annealing. The “K” factor variation ranging from 0. Nature of the grain boundary and stress corrosion cracking (SCC) The grain boundary energy in type 304 stainless steel is known ( Murr 1975) to vary from 20 to 835 mJ/m 2. The tag of AISI on it stands for (American Iron and Steel Institute), identifying its commercial availability of stainless steel or chromium steel. 5% chromium. One item of note: The K factor found in the "Machinists Handbook" (Industrial Press Inc. 03 m/s) and different loads (6 N, 15 N) with and without lubricant (liquid vaseline) were carried out. More Details About Each Stainless Steel Grade. Grade 440C stainless steel is a high carbon martensitic stainless steel. Over small temperature ranges, the thermal expansion of uniform linear objects is proportional to temperature change. JIS G 4305, Cold-rolled stainless steel plate, sheet and strip [9] EN 10151, Stainless steel strip for springs ? Technical delivery conditions [10] ISO 9444-1, Continuously hot-rolled stainless steel ? Tolerances on dimensions and form ? Part 1: Narrow strip and cut lengths [11] ISO 9444-2, Continuously hot-rolled stainless steel ? Tolerances. 1 \text { mm} 2. Diameter. This name has been derived from the composition of Chromium and Nickel elements present in the alloy. Alloy 304 is the most versatile and widely used alloy in the stainless steel family. It has excellent drawing properties and very good formability, while it is also highly corrosion-resistant. The high corrosion resistance, non-magnetic properties, and ability to withstand extreme temperatures make Grade 304 Stainless Steel suitable for use in a variety of industrial sectors. Stainless Steel. 316 SS: Performs best in temperatures above. This form of grade 301 may be used in. Below is a chemical breakdown of 304 steel: <=0. For tubing of 304 / 304L stainless steel, replace SS in the ordering number with 304L. 36 It is easy to scale-up and offers stability for long-term operation of MFCs. Zinc Plated Steel. q / A = [(17 W/(m K)) / (2 10 -3 m)] (80 o C)The K-factor is the most popular way of calculating the bend allowance and bend deduction, but there are multiple ways that this calculation can be done. In this study, the notch effect of different types of 304 stainless steel rod notch is studied because of the problem of difficulty in measuring the notch root strain of 304. 201 / 201LN. Availability Types 304 and 304L stainless steels have been produced in the form of plates, strip, sheets, bars, tubing, pipe, shapes and forgings, and any such K Factor in sheet metal bending is a constant used to calculate sheet metal flat length or Flat-pattern. The friction coefficient - λ - can be calculated by the Colebrooke Equation : 1 / λ 1/2 = -2,0 log 10 [ (2,51 / (Re λ 1/2 )) + (k / d h ) / 3,72 ] (11) . If ɛ r is roughness of pipe (mm) and D is the diameter of pipe (mm), then relative roughness can be expressed. 9 Bare Steel; DIN 7984-A2 Stainless Steel; Keys. Special analysis and proprietary alloys may have numbers that resemble AISI type numbers. ) and most stainless (304 etc. X 6 CrNiMo 17-12-03. When selecting a stainless steel for any corrosive environment, it is always best to consult with a corrosion engineer and, if possible, conduct tests. The diagram below indicates friction loss for water flow through ASME/ANSI B36. Essentially non-magnetic, becomes slightly magnetic when cold worked. See moreSo we bend a lot of mild steel. ASTM A193/A193M B16 2 1/2 & under 125,000 105,000 C35 A chromium-molybdenum-vanadium alloy used for high. What is austenitic stainless steel? Well, this group consist of themicrostructured andface-centered cubically crystal structured stainless steel. 2. Can someone explain how to properly setup and use a k-factor based bend table. Its nominal composition is 18% chromium and 8% nickel, so it is also called 18/8 stainless steel. vii 19. An alloy steel is a high-strength carbon steel that can be heat treated up to 300 ksi. The density of stainless steel 304 is 7. Chromium and nickel give stainless steel its stain resistance and attribute to the hardness of the metal. 75 for the 304L when compared to 304 [25], so sensitization takes longer to start in the 304L, as expected. 779: 122. 1 mm can be made in polypropylene PP, aluminum or stainless steel. STAINLESS STEELS 301 16. Due to its composition, corrosion and heat resistance and its mechanical properties, grade 304 is used in all fields of industrial, commercial and domestic manufacturing. Let's calculate the K-factor for a metal sheet having a thickness of 1 \text { mm} 1 mm and bent to an angle of 90^\circ 90∘. Low carbon content means less carbide precipitation in the heat-affected zone during welding and a lower susceptibility to intergranular corrosion. Steel Cold Rolled 200 (93) . 3-0. 17-4 PH is more resistant to chloride-induced stress corrosion cracking (SCC) than 304 stainless steel, making it ideal for coastal and marine applications. Tank Material:304 Stainless Steel Note:€For low quantity purchases, enclosed truck can be requested Housing Material:304 Stainless Steel w/ Corrosion Resistant Cover Band, RemovableWe are going to review three bending scenarios with three different bending angles; 60, 90 and 120, and we will calculate K-Factor, Bend Allowance and Bend Deduction for them. More info. 304 Stainless Steel – 14 gauge ( 0. By continuing to browse this site you agree to our use of cookies. AISI 304 (1. It is calculated on the basis of the chromium (Cr), molybdenum (Mo), tungsten (W), and nitrogen (N) content of an alloy. 73-Rubber (60 A Belt) Tool Steel . 4310 stainless steel physical properties, including density, specific heat capacity, electrical resistivity, modulus of elasticity, thermal conductivity, and coefficient of thermal expansion. His paper was a compilation and critical analysis of the values of 2 that had been published TENSILE STRESS-STRAIN RESULTS FOR 304L AND 316L STAINLESS STEEL1 PLATE AT TEMPERATURE R. 73 °F: Melting Point: 1673: 1723: K: 2551. 0. The chemical composition of SS304 and SS316 is the primary factor that sets them apart. 15: 640 304 stainless steel (annealed) 0. 5: Tantalum: 6. 1. 456. If cost is a prime factor, 410. In the process of making stainless steel, alloying elements such as chromium (Cr), nickel (Ni), manganese (Mn), silicon (Si), titanium (Ti), and molybdenum (Mo) are added to improve its performance and make it resistant to corrosion, or rust-free. - iron. F: Thermal Conductivity: 14: 17: W/m. Resistance to corrosion in oxidizing environments is a result of the 18 to 19% chromium that the 304 alloys contain. ASTM A193/A193M B8M Class 2 3/4 & under over 3/4 to 1. 4301). Stainless steel 304 is an austenitic grade that can be severely deep drawn. I’d like to review K-Factor and how K-Factor applies to your sheet metal designs. 94 mm )In order to better understand the role of uranium on the corrosion behavior of stainless in aqueous nuclear fuel reprocessing and decontamination operations, 304L stainless steel coupons were treated with nitric acid media at 45 °C and 90 °C in the presence of 0. In this instance 304L is recommended due to its resistance to carbide precipitation. 3 1. 030" 0. 304 0,07 1,00 2,00 0,045. Calculation of K-Factor for 304 stainless steel bent sheets. ₹ 60 / Kg. 4. Nickel amounts to about 8% and Chromium accounts for about 18%. tR = tF + 459. Two surface finishing conditions. Please note that because of the variation in roughness in these materials depending on the source, the roughness values reported here have uncertainties ranging from ± 20 % for new wrought Iron to ± 70 % for riveted steel. Contact Supplier. The corrosion resistance of stainless steels means that the surface characteristics, including frictional properties, are unlikely to be affected in service due to corrosion issues, provided the correct grade has been selected. The austenitic Types 309 and 310, containing. 40 mm 0. 5% chromium. e. The emissivity of stainless steel 316L with surface roughness 4. Lawrence Convention Center, Pittsburgh (2003) 26. 304 stainless steel (304ss) is the most employed material in the water supply system (WSS), due to its attractive combinations of mechanical properties and corrosion resistance [1, 2]. It is still sometimes referred to by its old name 18/8 which is derived from the nominal composition of type 304 being 18% chromium and 8% nickel. 2. Type 439 is a titanium stabilized, 18 percent chromium alloy that may be used in many oxidizing environments where Type 304 is considered adequate in terms. 304 -1. 463 0. Reply. To learn more about the differences among stainless steels, feel free to read our article on the type of stainless steel. Stainless Steel Visit our Website at Types 302, 304, 304L, 305 RESISTANCE TO CORROSION General Corrosion The Types 302, 304, 304L and 305 austenitic stainless steels provide useful resistance to corrosion on a wide range of moderately oxidizing to moderately reducing environments.