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Stainless steel has added nickel, chromium and many other alloying elements that other types of steel lack. This difference has resulted in corrosion resistance, high thermal conductivity, ductility and many other superior properties. In this article, MRS Steel will delve deeper into Ferritic stainless steel to examine its strength and applications in construction.1. What is Ferritic stainless steel?Ferritic stainless steel, also known as low carbon steel containing about 12-20% chromium, is a straight, non-hardening chromium stainless alloy with a carbon content below 0.2%. After undergoing special heat treatment, mills produce Ferritic stainless steels including: 409, 430, 430 LI, 434, 439, 442, 444, 446,... stainless steelFerritic steels are unique in that they contain higher chromium content than other types of stainless steel, which can be up to 27%. However, in some cases the chromium content is only equivalent to Austenitic. Additionally, most Ferritic steels are also nickel-free, similar to Martensitic steel.2. Characteristics of Ferritic stainless steel Resistant to stress corrosion crackingStress corrosion cracking (SCC) occurs due to corrosive environments and tensile stresses leading to crack formation. This process significantly reduces the load-bearing capacity of the metal structure. Austenitic stainless steel is highly vulnerable to SCC due to its interaction with chloride-rich environments. However, the structure of Ferritic is resistant to high levels of SCC, making it an excellent choice for applications in harsh environments or those containing high chloride levels.Ductility and FormabilityThe carbon content determines the ductility and brittleness of steel, while Ferritic steel only contains below 0.2% carbon, which provides it with moderate ductility and ease of shaping. Its low carbon content also helps prevent cracking and breakage during shaping. However, the low carbon content can lead to issues like cracking during welding and the inability to harden the steel using conventional heat treatment methods.Low thermal expansion Thermal expansion is a physical property representing the change in size of a during heat exchange. A high coefficient of thermal expansion can lead to cracking when there are temperature differences. Ferritic steel has a low coefficient of thermal expansion that helps fix the dimensions of the metal, making it suitable for high-temperature applications.High thermal conductivityCompared to other common steel types, Ferritic stainless steel stands out with its excellent thermal conductivity. Therefore, they are also widely used in furnace and boiler heat exchangers as well as other heat transfer components.High Oxidation ResistanceFerritic steel is also known for its good oxidation resistance, especially at high temperatures. The chromium oxide film protects steel from rust external rusting factors. In Vietnam, factories also enhance the oxygen resistance of Ferrit steel by adding silicon or aluminum.3. Ferritic stainless steel classification and equivalent applicationsDepending on the composition and application, Ferritic stainless steel is divided into 5 groups including:Group 1 (Type 409/410 L)This is the group of Ferrite steels with the lowest chromium content, so the price is also much cheaper among all types of stainless steel. Type 409 is often used as catalytic converter housing or the main application of type 410 L is LCD screen frames, buses,...Group 2 (Type 430)Type 430 Ferritic stainless steel has a chromium content ranging from 16-18%, providing better corrosion resistance than Group 1. It is widely used in the production of washing machines, kitchen furniture,... Additionally, with similar properties and strength, 430 Ferrit steel can replace 304 stainless steel in various applications, such as cladding.Group 3 (Type 430TI, 439, 441)Group 3 has a chromium content of 17.5 - 18.5%, offering excellent welding and shaping properties, even superior to 304 stainless steel. This group is commonly used in exhaust systems, sink basins,…Group 4 (Type 434, 436, 444)Group 4 stands out with its high corrosion resistance thanks to the addition of Molybdenum in the composition. For example:- Inox 434: 16.0% – 18.0% chromium; 0.9% < Mo < 1.4%- Inox 436: 16.0% – 18.0% chromium; 0.9% < Mo < 1.4%; 0.3% < Ti < 0.6%- Inox 444: 17.0% – 20.0% chromium; 1.8% < Mo < 2.5%They are suitable as materials for applications in high-corrosion environments, water tanks, ovens and outdoor products.Group 5 (Type 446, 445)This group has the highest chromium and molybdenum content of all Ferritic stainless steel groups, which corresponds to their excellent corrosion and rust resistance. In practice, Ferritic steel types 446 and 445 are used specifically for heat exchanger components, water heaters, pressure cookers,...Vietnam has abundant iron ore resources and crude steel output ranks 13th globally. With improvements in production technology and a modern, closed chain system, Vietnam stainless steel is committed to meeting international standards and strict requirements from customers. Importers can contact MRS Steel via Whatsapp: +84 76 911 2358 for advice on the Vietnamese steel market and products.

Austenitic stainless steel stands out for its strength, corrosion resistance, high aesthetics, ease of production and maintenance. That is also the reason why they become the top choice for construction and many other industries.1. What is Austenitic steel?Austenitic is a type of stainless steel that contains austenitic (gamma iron, gamma-phase iron). Thanks to the high ratio of nickel and chromium, Austenitic steel is easily formable, weldable into various shapes and possesses excellent strength and corrosion resistance.2. What are the characteristics of Austenitic stainless steel?Austenitic stainless steel is one of the popular steel types, accounting for three-quarters of the global stainless steel market. They possess many outstanding features such as:Durability at temperatureAustenitic stainless steel can withstand high temperatures up to 1900 degrees F but some types can deform at temperatures of 800 degrees F.Cold working capabilitiesAustenitic steel cannot be hardened by conventional heat treatment and requires cold working to increase its strength. The steel is annealed before being rapidly cooled to return it to its original state. Thanks to that, Austenitic stainless steel has better hardness, durability and aesthetics.Low thermal conductivityAustenitic stainless steel has lower thermal conductivity than other types such as Ferritic.Shaping abilityThanks to its high nickel and chromium content, Austenitic steel is easy to shape and suitable for many different applications.3. Classify Austenitic stainless steel by seriesAustenitic stainless steel is divided into many series based on composition such as series 200 (SUS 201, 202,...) and series 300 (SUS 301, 304, 316, 316L, 321, 310s,...). For group 300, which usually contains 10.5% chromium and 8% nickel, the most popular is 304 stainless steel with high standards, safe for health and environmentally friendly. Meanwhile, series 200 contains less chromium, nickel and adds nitrogen, manganese, so it has a lower price than series 300.Application of Series 300Aerospace tubesStorage boxTankFood and Beverage EquipmentPharmaceutical equipmentMining equipment and chemicalsCutleryFurnace Application of Series 200Family water tankWashing machineDishwasherCooking utensils and cutleryCar partsIndoor architecture4. Applications of Austenitic stainless steelAustenitic steels have become a familiar material in many industries including medical, automotive, aerospace,... They are known for their outstanding strength, durability and formability.Medical applicationsTo ensure safety, medical tools such as surgical needles, injection needles, cotton boxes, tweezers, scissors, medicine trays,... are all made from Austenitic stainless steel.Automotive manufacturing Many car parts are made from Austenitic stainless steel for greater strength and aesthetics. In addition, in the fuel rail system, drainage holes or deep drawing parts are also made from Austenitic steel.Industrial and consumer applicationsKitchen appliances including sinks, refrigerators, kitchen shelves,... or generator parts and springs are all made from cold-processed Austenitic stainless steel.Aerospace applicationsCold processing technology of Austenitic stainless steel meets military and aerospace application requirements such as manufacturing jet engine components, helicopters, landing gears,...5. Where to import Austenitic stainless steel?Austenitic is the most common type of stainless steel with high applicability in production and life. Demand for Austenitic stainless steel has increased recently as industries and manufacturing sectors gradually recover and stabilize after the COVID-19 pandemic.Vietnam is one of the addresses for importing Austenitic stainless steel that is trusted by many partners. Possessing a modern production process, stable input material sources, advanced machinery systems Tenova, Danieli,... help finished products meet international standards and customer requirements. In addition, Vietnam also has many advantages in price thanks to abundant labor resources, import-export policies, anti-dumping duty incentives,… As a result, importers can access quality steel at the most reasonable prices.For detailed advice and quotes, please contact MRS Steel via Whatsapp:+84 76 911 2358 for the most thoughtful support!

Stainless steel is famous for its resistance to corrosion and rust thanks to its Chromium and Nickel content of over 12% while its carbon content is very low (below 0.1%). However, under harsh environmental conditions, stainless steel can be affected. So what factors can cause corrosion or rust in stainless steel?1. Why Stainless Steel is Rust ResistantWhen exposed to air, chromium in stainless steel reacts with oxygen to form a very thin layer of chromium oxide that cannot be seen with the naked eye. They act as an extremely strong protective layer and are completely unaffected by water and air. Therefore, the stainless steel is almost completely protected against rust or oxidation.2. Top 5 Factors Causing Stainless Steel Corrosion2.1. Strong chlorides can cause pitting corrosion on stainless steelSome types of stainless steel alloys will corrode extremely when exposed to chloride-rich environments. 304 stainless steel is often used to make specialized equipment serving the navy. During long-term use, the metal begins to pit due to exposure to salt-rich seawater or airTo prevent this situation, manufacturers use stainless steel with special chloride resistance, such as type 316. In addition, the stainless steel surface should be coated with a specialized layer to prevent the alloy from coming into contact with chloride environments.2.2. Galvanic corrosion caused by welding different stainless steel alloysOne of the most common mistakes that leads to corrosion of stainless steel is welding different metal wires or plates together. The reason is that each type of material has different properties, so when connected through a common electrolyte material, an electric current will flow from one material to the other. This makes it easier for the metal to become an "anode" and accelerates the corrosion process. Corrosion speed also depends on other factors such as the type of stainless steel being welded, the type of welding material, temperature, sensitivity, exposed metal surface area,...The best way to prevent galvanic corrosion from welding is to avoid connecting two different metals or to seal the weld with a specialized coating to prevent the flow of electrons from the cathode to the anode.2.3. Coating normal iron or steel onto stainless steelIn some applications, billet or iron residue existing on the surface of stainless steel can break down the protective oxide layer of the stainless steel billet, losing its corrosion resistance and becoming rusty.Factories need to thoroughly clean welding and cutting equipment, tools or steel brushes before moving on to process new materials. This will limit metallic chips from metals sticking to the stainless steel surface.2.4. Applying extremely high temperatures to stainless steelStainless steel alloys have very high melting points, around 1400 - 1500 degrees Celsius. However, if stainless steel is exposed to high temperatures, it can undergo physical and mechanical changes, affecting its corrosion resistance. For example, steel alloys exposed to high temperatures during the annealing treatment process can appear to scale and flake off, causing bimetallic corrosion. In addition, too high temperatures also lose the protective oxide layer, increasing the risk of corrosion.Mills control this corrosion factor by testing the appropriate operating temperature for each grade of stainless steel to see if the temperature used exceeds the limit.2.5. Other environmental factorsThere are many cases where factories can produce stainless steel products to custom specifications to meet customer needs. This accidentally leads to stainless steel being corroded due to some unforeseen environmental factors. For example, products that will be used in coastal areas have higher than normal humidity and chlorides, which will accelerate metal corrosion.Therefore, when choosing stainless steel as a material for applications, manufacturers must take into account environmental factors to ensure products with good corrosion resistance and durability.Hopefully, this article on factors that cause stainless steel corrosion has helped you learn more ways to better protect your products. If you have any questions or need to import Vietnamese stainless steel at good prices and quality, please contact MRS Steel via Email: vanloc@mrssteel.com.vn or Whatsapp:+84 76 911 2358.