Independent Specialists in Stainless Steels and Nickel Alloys since 1998.
317L / 1.4438
317L is a type of stainless steel alloy known for its excellent corrosion resistance and high strength. It is commonly used in applications requiring exposure to harsh environments.
317L (also known as UNS S31703 or 1.4438) is a type of stainless steel alloy known for its excellent corrosion resistance and high strength. It is a low carbon, molybdenum-bearing austenitic stainless steel that is commonly used in applications requiring exposure to harsh environments.
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One of the key characteristics of 317L is its ability to resist corrosion in a wide range of environments. This includes resistance to both organic and inorganic acids, as well as resistance to chlorides and other halides. It also has good resistance to pitting and crevice corrosion. This makes it a popular choice for use in chemical processing, oil and gas production, and other industries where corrosion resistance is a key requirement.
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In addition to its corrosion resistance, 317L also has high strength and good formability. It has a higher yield strength than most other austenitic stainless steels, making it a good choice for applications that require high strength. It also has good formability, which makes it easy to work with during fabrication.
317L is commonly used in a variety of applications, including:
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Chemical processing: The excellent corrosion resistance of 317L makes it a popular choice for use in chemical processing equipment, such as tanks, vessels, and heat exchangers.
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Oil and gas production: 317L is often used in oil and gas production equipment, including pipelines and offshore platforms, due to its ability to resist corrosion in harsh environments.
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Pharmaceuticals and food processing: The corrosion resistance and non-toxic properties of 317L make it a popular choice for use in pharmaceutical and food processing equipment.
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Power generation: 317L is often used in power generation equipment, such as boilers and heat exchangers, due to its high strength and corrosion resistance.
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Overall, 317L is a versatile and reliable stainless steel alloy that is well-suited for a wide range of applications where corrosion resistance and high strength are required.
Chemical Composition of 317L / 1.4438
The chemical composition of 317L, also known as UNS S31703 or 1.4438, is as follows:
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Carbon (C): 0.03% max
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Manganese (Mn): 2.00% max
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Silicon (Si): 1.00% max
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Phosphorus (P): 0.045% max
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Sulfur (S): 0.03% max
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Chromium (Cr): 18.0-20.0%
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Nickel (Ni): 11.0-15.0%
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Molybdenum (Mo): 3.0-4.0%
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Nitrogen (N): 0.1-0.22%
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Iron (Fe): balance
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317L alloy is a low carbon, molybdenum-bearing austenitic stainless steel, that is known for its excellent corrosion resistance and high strength.
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It's Chromium content gives it a good resistance to pitting and crevice corrosion and the high nickel and molybdenum content give it an excellent resistance to chloride pitting and general corrosion.
The low carbon content of 317L alloy make it less susceptible to carbide precipitation during welding, which makes it a good choice for use in chemical processing equipment and other applications where corrosion resistance is a key requirement.
The physical and mechanical properties of 317L, also known as UNS S31703 or 1.4438, are as follows:
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Physical Properties:
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Density: 7.97 g/cm3
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Melting Point: 1454°C (2650°F)
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Mechanical Properties:
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Ultimate Tensile Strength: 515 MPa
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Yield Strength (0.2% offset): 205 MPa
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Elongation at Break: 40%
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Hardness (Brinell): 217 max
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Hardness (Rockwell B): 95 max
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317L alloy is known for its high strength and excellent corrosion resistance. It has a higher yield strength than most other austenitic stainless steels, which makes it a good choice for applications that require high strength. Additionally, its elongation at break of 40% and its ductility give it a good formability.
The alloy is commonly used in application that require high strength and corrosion resistance, such as chemical processing, oil and gas production, and other industries.
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It's important to note that the mechanical properties of 317L alloy can vary depending on the specific conditions in which it is being used, such as the temperature, the amount of stress, and the rate of loading. Therefore, it's always best to consult the manufacturer's data sheet for specific information about the alloy's properties in a given application.
Physical & Mechanical Properties of 317L / 1.4438
Variants of 317L
There are a few variants of 317L stainless steel alloy, which are designed to offer specific properties or to meet specific requirements.
Some of the common variants of 317L include:
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317LN: This variant of 317L is designed to have higher levels of nitrogen, which improves its corrosion resistance and increases its strength. It is commonly used in applications that require exposure to chloride-containing environments, such as in the oil and gas industry.
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317LMN: This variant of 317L is designed to have higher levels of molybdenum and nitrogen, which improves its corrosion resistance and increases its strength. It is commonly used in applications that require exposure to chloride-containing environments, such as in the oil and gas industry.
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317Lmod: This variant of 317L is designed to have higher levels of molybdenum, which improves its corrosion resistance and increases its strength. It is commonly used in applications that require exposure to chloride-containing environments, such as in the oil and gas industry.
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317L+Mo: This variant of 317L is designed to have higher levels of molybdenum, which improves its corrosion resistance and increases its strength. It is commonly used in applications that require exposure to chloride-containing environments, such as in the oil and gas industry.
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It's important to note that the specific properties of each variant of 317L can vary depending on the manufacturer, so it's always best to consult the manufacturer's data sheet for specific information about the alloy's properties in a given application.
AVAILABLE FORMS
Intamet offers 317L in a wide range of forms, including the below:
