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316 Stainless Steel: Definition, Composition, Properties, Processing, Applications, and More
- John
What is 316 Stainless Steel?
316 stainless steel (also called A4 or 18/10) is the second most commonly used austenitic stainless steel after 304/A2 stainless steel with a face-centered cubic (FCC) crystal structure. Its primary composition contains 16-18% chromium, 10-14% nickel, and 2-3% molybdenum. 316 meets standards such as ASTM A240 with equivalent grades like 1.4401 (EN) and SUS 316 (JIS). It has excellent corrosion resistance, particularly against chlorides, and is widely used in marine environments, chemical processing, medical devices, etc. Common variants include 316L and 316H. 316 is often processed through cold working to gain high strength that is similar to duplex stainless steel, though not as high.
Chemical Composition of 316 Stainless Steel
Check the table below for the chemical composition of 316 stainless steel:
| Chromium, Cr | Nickel, Ni | Molybdenum, Mo | Manganese, Mn | Silicon, Si | Carbon, C | Phosphorus, P | Sulfur, S | Nitrogen, N | Iron, Fe |
| 16-18% | 10-14% | 2-3% | ≤ 2.00% | ≤ 0.75% | ≤ 0.08% | ≤ 0.045% | ≤ 0.030% | ≤ 0.10% | Balance |
Properties of 316 Stainless Steel
Here are three major reasons that make 316 stainless steel unique:
- Excellent corrosion resistance in harsh environments.
- High strength and durability at elevated temperatures.
- Non-magnetic in its annealed state for specific applications.
Physical Properties
Check the table below for the core physical properties of 316 stainless steel:
| Property | Typical Value (Metric/Imperial) | Performance |
| Density | 8.00 g/cm³ (0.289 lb/in³) | High; contributes to the overall strength |
| Melting Point | 1370 – 1400 °C (2500-2550°F) | High; suitable for high-temperature applications |
| CTE, Linear (20℃) | 16.0 µm/m°C (8.89 µin/in°F) | Moderate; compatible with various materials |
| Specific Heat Capacity (0-100°C/32-212°F) | 500 J/kg·K (0.12 BTU/lb·°F) | Adequate; reduces temperature fluctuations |
| Thermal Conductivity (100°C) | 16.3 W/m·K (9.4 BTU/hr·ft·°F) | Moderate; allows for controlled heat transfer |
| Electrical Conductivity | 1.45% IACS (0.84 MS/m) | Low; suitable for insulation purposes |
| Magnetic Properties | Non-magnetic (in the annealed condition) | Provides magnetic neutrality, ideal for sensitive applications. |
Mechanical Properties
Check the table below for the core mechanical properties of 316 stainless steel:
| Property | Value (Metric/Imperial) | Performance |
| Tensile Strength | 580 MPa (84.1 ksi) | High strength, suitable for structural use compared to common steels. |
| Yield Strength | 290 MPa (42.1 ksi) | Moderate yield strength, lower than some high-strength alloys. |
| Rockwell Hardness | 79 HRB | Relatively soft compared to harder steels like tool steel. |
| Elongation at Break (in 50 mm) | 50% | Excellent ductility, higher than many steels, good for forming and bending. |
| Young’s Modulus (in tension) | 193 GPa (28 msi) | Stiff, but slightly less than carbon steels, ensuring durability under load. |
Chemical Properties
Check the table below for the core chemical properties of 316 stainless steel:
| Chemical Property | Description | Performance |
| Corrosion Resistance | Ability to resist chemical attack, particularly in harsh environments. | Excellent, especially in chloride-rich environments; better than 304 steel. |
| pH Sensitivity | Tendency to react with acids or bases. | Resistant in a wide pH range, including acidic and mildly alkaline environments. |
| Reactivity | Tendency to react chemically with other substances. | Low reactivity; stable in most chemical environments. |
| Oxidation Resistance | Ability to resist oxidation at high temperatures. | High; maintains oxidation resistance up to 870°C (1598°F). |
| Passivation | Formation of a protective oxide layer on the surface. | Strong; the passive layer regenerates quickly, protecting against corrosion. |
| Combustibility | Tendency to burn or catch fire. | Non-combustible; does not burn or contribute to fire hazards. |
| Flammability | Likelihood of igniting under specific conditions. | Non-flammable; no ignition risk under normal environmental conditions. |
Heat & Corrosion Resistance
Heat Resistance
316 stainless steel offers good heat resistance. It can work up to 870°C for intermittent use and 925°C for continuous use in non-corrosive environments. When used between 425°C and 860°C, 316 is prone to carbide precipitation, which reduces its corrosion resistance.
316L is preferred for such conditions due to better resistance to carbide precipitation; 316H provides improved strength at high temperatures above 500°C.
Corrosion Resistance
316 stainless steel offers excellent corrosion resistance, especially against chloride-induced pitting, making it ideal for marine and coastal environments. The presence of molybdenum in the alloy boosts its protection against chloride-related damage.
However, it is not immune to all corrosion types and can still suffer pitting, crevice corrosion, and stress corrosion cracking in warm seawater or chloride-rich conditions above 60°C. Even so, it performs better than 304 stainless steel in most corrosive situations and is commonly used in chemical plants, food processing, and marine settings.
Processing of 316 Stainless Steel
Forming
316 stainless steel has excellent formability because of its high nickel and molybdenum content. These elements increase its flexibility and resistance to corrosion, reducing the chance of cracking during shaping. Its austenitic structure also helps it stay flexible during both cold and hot forming, making it easier to create complex shapes.
Welding
316 stainless steel offers good weldability and is compatible with most common methods. It retains its strength and corrosion resistance after welding.
However, there’s a risk of intergranular corrosion, particularly at high temperatures. In this case, 316L is often preferred, as it reduces the risk of carbide formation. Using appropriate filler metals and techniques can further enhance weld quality and prevent corrosion.
Machining
316 stainless steel has moderate machinability and is harder to machine than grades like 304 due to its toughness and work-hardening tendency.
Tools wear out faster, especially high-speed steel ones, so carbide tools are recommended for better efficiency and durability. Good cooling and lubrication help prevent overheating and improve surface finish. Slower cutting speeds and shallow cuts are useful to manage its work-hardening during machining.
Heat Treatment
316 stainless steel is typically solution annealed at 1,040°C – 1,120°C (1,900°F to 2,050°F), then rapidly cooled (usually water quenched) to maintain corrosion resistance and optimize mechanical properties. Post-annealing, it cannot be hardened by heat treatment but only through cold working.
Avoid prolonged exposure in the 425°C to 860°C range to prevent carbide precipitation and intergranular corrosion.
Advantages and Disadvantages of 316 Stainless Steel
Here are the advantages and benefits of 316 stainless steel:
- Great corrosion resistance, especially in chloride-rich and harsh environments.
- Strong resistance to pitting and crevice corrosion; ideal for marine and chemical use.
- Good heat resistance; maintains strength and resists oxidation at high temperatures.
- Very durable, lasting a long time even in tough conditions.
- Easy to weld, making it practical for many projects.
Here are the disadvantages and limitations of 316 stainless steel:
- More expensive than 304 stainless steel, making it less affordable for some uses.
- Can crack under stress in chloride environments at high temperatures.
- Can stain in warm seawater if not maintained properly.
- Harder to machine, meaning more time and cost to work with.
- Less available in some markets compared to other types of stainless steel.
Common Applications of 316 Stainless Steel
Check the table below for a quick view of its common applications:
| Industry | Application | Why it suits |
| Marine Engineering | Ship components, Fasteners, Propeller shafts, Valves | Corrosion resistance in saltwater environments |
| Chemical Processing | Reactors, Heat exchangers, Storage tanks, Pumps | Resistant to chemicals and acids |
| Food & Beverage | Processing equipment, Storage tanks, Conveyors, Cutlery | Non-reactive with food, easy to clean, corrosion-resistant |
| Pharmaceutical | Surgical instruments, Sterilizers, Bioreactors, Storage tanks | Hygienic, corrosion-resistant, easy to sterilize |
| Oil & Gas | Pipework, Valves, Offshore rigs, Heat exchangers | High corrosion resistance under extreme environments |
| Automotive | Exhaust systems, Fuel lines, Fasteners, Manifolds | Heat and corrosion resistance |
Equivalent Grades of 316 Stainless Steel in Different Countries and Regions
Here are some common equivalent grades of SS 316 in different countries and regions:
| Country/Region | Standard/Specification | Equivalent Grade |
| China | GB/T 20878 | 0Cr17Ni12Mo2 |
| USA | ASTM A240 | 316 |
| EU | EN 10088-1 | X5CrNiMo17-12-2 (1.4401) |
| Germany | DIN 17440 | X5CrNiMo17-12-2 |
| Russia | GOST 5632 | 08KH16N11M3 |
| Japan | JIS G4303 | SUS316 |
| England | BS 970 | 316S31 |
Variants of 316 Stainless Steel
Common variants of 316 stainless steel are listed in the table below:
| Variant | What is it | Why might it be chosen instead of 316? |
| 316L | Lower carbon version of 316. | Better for welding and avoiding corrosion. |
| 316H | Higher carbon version of 316. | Stronger at high temperatures. |
| 316Ti | Titanium-stabilized 316. | More resistant to high-temp corrosion. |
| 316N | Nitrogen-enhanced 316. | Higher strength and corrosion resistance. |
| 316F | Sulfur-added 316 for machining. | Easier to machine for precision parts. |
| 316LN | Low carbon, nitrogen-enhanced 316. | Stronger and more resistant to sensitization. |
*Note:
- The most common 316 variants are 316L, 316H, and 316Ti, used for welding, high-temperature strength, and resistance to intergranular corrosion. Less common variants like 316N, 316F, and 316LN are for more specialized applications.
- Sensitization occurs when stainless steel is heated to 450-850°C, forming chromium carbides at grain boundaries, which reduces intergranular corrosion resistance. Good resistance prevents this issue and helps avoid weld area corrosion.
- 316L, 316H, and 316Ti generally have better resistance to sensitization among the variants.
- 316F is designed with added sulfur for better machinability, but this can slightly reduce its corrosion resistance compared to other variants.
Which Is Better, 316 or 316L?
316L is better for corrosion resistance due to its lower carbon content, making it more suitable for welding and high-temperature applications than 316.
Is 316L More Expensive Than 316?
Yes, 316L is slightly more expensive than 316, but the price difference is minimal due to their similar composition. The higher cost is mainly due to 316L’s lower carbon content, which improves corrosion resistance and weldability.
304 vs 316 Stainless Steel
Grade 304 is typically more commonly used than grade 316, though they are very similar in many aspects. The biggest difference between them is the proportion of molybdenum, which makes 316 more corrosion-resistant than 304.
Check the table below for a quick comparison between 316 and 304 stainless steel:
| Property | 304 | 316 |
| Chemical Composition | Cr: 18-20%, Ni: 8-10.5% | Cr: ≤ 18%, Ni: ≤ 14%, Mo: ≤ 3% |
| Corrosion Resistance | General resistance, suitable for normal environments | Higher resistance, especially in chloride and marine environments |
| Applications | Kitchen utensils, automotive trim, building materials, etc. | Chemical, marine, pharmaceutical equipment, etc. |
| Cost | Lower | Higher |
What You Might Also Concern
Now that you have a deeper understanding of 316 stainless steel, there are still some common issues that deserve your attention：
Is 316 Stainless Steel Magnetic?
316 stainless steel is non-magnetic because its austenitic structure is stabilized by nickel. However, cold working can slightly increase its magnetism by distorting the structure.
Related Reading
Is Stainless Steel Magnetic?
Can 316 Stainless Steel Rust?
Yes, 316 stainless steel can rust, but it is highly resistant to corrosion, especially in harsh environments. Rusting is rare but possible in extreme conditions.
Related Reading
Will Stainless Steel Rust and How Can You Solve It?
Which is Better, 304 or 316 Stainless Steel?
It depends on the specific requirements of the application. 316 stainless steel is more corrosion-resistant, especially in harsh environments, while 304 is more cost-effective and suitable for general purposes.
Further Reading
304 vs 316 Stainless Steel: Composition, Properties, Processing, Applications, Cost, and More
Is 316 Stainless Steel Good for Jewelry?
Yes, 316 stainless steel is good for jewelry. It’s hypoallergenic, resistant to tarnish and corrosion, and durable, making it ideal for long-lasting, low-maintenance jewelry.
Related Reading
Will Stainless Steel Tarnish or Fade?
Is 316 Stainless Steel Good for Watches?
Yes, 316 stainless steel is excellent for watches. It offers high corrosion resistance, durability, and a sleek appearance, making it ideal for long-lasting, high-quality watch casings and bands.
Is 316 Food Grade?
Yes, 316 stainless steel is considered food grade. It is commonly used in food processing and storage due to its superior corrosion resistance, particularly against acidic and salty foods.
Why Is 316 Stainless Steel So Expensive?
316 stainless steel is more expensive due to higher nickel and molybdenum content, which improves corrosion resistance but increases production costs compared to other grades like 304.
Summary & Furthermore
This article briefly explains the definition, composition, properties, processing characteristics, applications, and other important aspects of 316 stainless steel. To learn more about stainless steel or other steel types, check out our blog or contact our metal experts.
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